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Full text of "Flora of the southeastern United States;being descriptions of the seed?plants, ferns and fern?allies growing naturally in North Carolina, South Carolin, Georgia, Florida, Tennessee, Alabama, Mississippi, Arkansas, Louisiana and the Indian territory and in Oklahoma and Texas east of the one?hundredth meridian /by John Kunkel Small ..."

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\ 



FLORA 



t * 



OF THE 



SOUTHEASTERN UNITED STATES 



BEING DESCRIPTIONS OF 



THE SEED-PLANTS, FERNS AND FERN-ALLIES GROWING NATURALLY IN 
NORTH CAROLINA, SOUTH CAROLINA, GEORGIA, FLORIDA, TENNESSEE, 

ALABAMA, MISSISSIPPI, ARKANSAS, LOUISIANA AND THE 

INDIAN TERRITORY AND IN OKLAHOMA AND 

TEXAS EAST OF THE ONE-HUNDREDTH 

MERIDIAN 



BY 



• JOHN KUNKEL SMALL, Ph.D. 



CURATOR OF THE MUSEUMS AND HERBARIUM OF THE NEW YORK BOTANICAL GARDEN 










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NEW YORK 




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PUBLISHED BY THE AUTHOR <^^ -^ G El 11/ ^Q^ 



1903 




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Copyright 1903 
By JOHN KUNKEL SMALL. 



** 



Press of 
The Hew Eaa PAtNTiiiG Compaky. 

Lancaster, Pa. 



PREFACE. 



The object of this Flora is to present descriptions of the seed-plants, ferns 
and fern-allies growing naturally within the southeastern United States as limited 
by the northern boundaries of North Carolina, Tennessee, Arkansas, Indian 
Territory and Oklahoma, and the one hundredth Meridian, together with the 
known geographical distribution of each species. The usual flowering-period is 
given after the geographical distribution, except in cases where plants bloom 
throughout the year. 

The arrangement of the higher plant-groups is essentially that of Engler 
and Prantl in their Natiirlichen Pflanzenfamilien, except where modifications 
of the sequence there adopted have seemed to be desirable. 

Analytical keys formed by the contrasting of diagnostic characters precede 
the descriptions of the families, genera and species, while a general key to the 
orders precedes the main body of the Flora. 

The collections on w^hich the work is based are mainly at the New York 
Botanical Garden, The manuscript of several groups has been prepared else- 
where by specialists, as indicated in the text. 

To the custodians of the larger herbaria of the country, I wish to express 
my thanks for opportunities afforded for the examination of specimens desirable 
for study, during the prosecution of my investigations. I also take pleasure in 
acknowledging important assistance by my associates. Dr. N. L. Britton, Prof. 
L. M. Underwood, Dr. P. A. Eydberg, Mr. G. V. Nash, Dr. J. H. Barnhart and 

F 

Mr. R. M, Harper ; by Mr. C. D. Beadle, Director of the Biltmore Herbarium 
and his associates ; by Prof. W. L. Bray, of the University of Texas, Mr. A. 31. 
Huger of North Carolina, Mr. A. Cuthbert of Georgia and Prof. S. W. Stanfield 



of Texas. 



J. K. Small 



The Neav York Botanical Garden, 

July 22, 1903. 



in 



CONTENTS. 

Page. 
vii-xii 

\ 1-1320 

Appendix 1321-1325 

List of Genera and Species published in this Flora 1326-1341 



Key to the Orders 
Descriptive Flora 



Table of the Orders and Families 
Index 



1342-1344 
1345-1370 



\ 



T 



KEY TO THE ORDERS. 



1 



[ants without flowers or seeds, but producing spores each of which, on germination, develops into 
a flat or an irregulur prothallium. The prothallia bear the reproductive organs (antheridia and 
archegonia). As a result of the fertilization of an egg in the archegonium by a 6i)erm produced in 
the antheridium a fern or an allied plant is developed. 

Page. 



I. PTERIDOPHYTA. 

Leaves with broad entire or dissected blades. (Fern-like plants.) 
Spores of one kind, minute. 

Vernation straight or inclined : prothallium subterranean, yellowish. 

Order Ophiog loss ales. 
Vernation circinate : prothallium terrestrial or epiphytic, green. Order Filicales. 

Spores of two kinds, minute microspores and larger macrospores, borne in sporocarps. 

Order Salviniales. 
Leaves scale-like or awl-like. (Moss-like or rush-like plants.) 

Sporangia in an apical cone, borne under peltate scales : stems hollow, rush-like. 

Order Equisetales. 
Sporangia in the axils of small or leaf-like bracts : stems solid. 

Leaves narrow or scale-like, flat, borne on erect or creeping stems : terrestrial plants. 

Order Lycopodiales. 
Leaves awl-like, often much elongated, borne on a short conn-like caudex : aquatic plants. 

Order Isoetales. 



1 



1 

3 

19 



20 



21 
24 



II. Plants with flowers which produce seeds. Microspores (pollen-grains) borne in microsporangia 
(anther-sacs) develop each into a tubular prothallium; a macrospore (embryo-sac) develops a 
minute prothallium, and together with the macrosporangium (ovule) in whifh it is contained, 
ripens into a seed. 



II. SPERMATOPHYTA. 

r 

Ovules and seeds borne on the face of a bract or a scale : stigmas wanting. 
Ovules and seeds in a closed cavity (ovar>"): stigmas present. 



25 

Class 1. Gymnospermae. 
Class 2. Angiospermae. 



1. Gymnospermae. 

r 

Plants growing by a single terminal bud, with pinnate leaves circinate in vernation : embryo pro- 
longed into a spiral. Order Cycadales. 25 

Plants growing by lateral as well as by terminal buds, with scale-like, flat or needle-like leaves 

not circinate: embryo not prolonged into a spiral. Order Pinales. 26 



2. Angiospermae. 

Cotyledon 1 : stem endogenous. 

Cotyledons normally 2 : stem exogenous (with rare exceptions) 



Subclass 1. Monocotyledones. 
Subclass 2. Dicotyledones. 



1. Monocotyledones. 



Perianth rudimentarj^ or degenerate, the members often bristles or mere scales, not corolla-like, 

or wanting. 
Flowers not in the axils of dr>' or chai!y bracts (scales or glumes). 

Perianth of bristles or chaffy scales. * Order Pandanales. 

Perianth fleshy or herbaceous, or wanting. 

Fruit baccate : endosperm present. Order Arales. 

Fruit drupaceous : endosperm wanting. Order Naiadales. 

Flowers in the axils of dry or chaffy, usually imbricated, bracts (scales or glumes). 

Order Poales. 
Perianth of 2 distinct series, the inner series usually corolloid. 

Gynoecium of distinct carpels. Order Alismales. 

Gynoecium of united carpels. 

Endosperm mealy. Order Xyridales. 

Endosperm fleshy, homy or cartilaginous. 

A. Ovary, and fruit, superior. .^.,t -, ^ 

a. Herbs, or rarely shrubs or trees, with simple leaves : ovules 2-many in each cavity of 
the ovary, or solitary only in the case of a few herbs. 
Inflorescence not a fleshy spadix. Order Liliales. 

Inflorescence a fleshy spadix subtended by a spathe. Order Arales. 



Prepared with the assistance of Dr. P. A. Kydberg. 



34 

225 
36 

48 

40 

231 



247 




Vll 



viii KEY TO THE ORDERS 

b. Trees or shrubs, with pinnately or palmately compound or lobed leaf-blades : ovules 

solitary in each cavity of the ovary. Order Arecales. z^\ 

B. Ovary, and fruit, wholly inferior or half-inferior. 

Endosperm present and usually copious. ,^.^^^00= 

Flowers regular : androecium not reduced. Order Amaryllidales. J85 

Flowers very irregular : androecium much reduced and modified. 

, '' Order Scitaminales. 307 

Endosperm wanting. ^ .^ 

Flowers regular, monoecious or dioecious : aquatic plants. Order Hydrocharitales. 46 
Flowers irregular, perfect: terrestrial or epiphytic plants. Order Orchidales. 308 

2. DiCOTYLEDONES. 

A. Corolla wanting, except in the pistillate flowers of Juglans (Juglandaceae). 

Calyx wanting, at least in the staminate flowers, except sometimes in Casuarina (Casuarinaceae). 

Herbs. 

Flowers mainly perfect. 

Seeds solitary in each carpel or in each cavity of the ovary : endosperm present. 

Flowers spicate : stvles wanting : stigmas sessile. Order Piperales. 330 

Flowers axillary: styles present. Callitrichaceae in Order Euphorbiales. 690 

Seeds numerous in each cavity of the ovary : endosperm wanting. 

Podostemaceae in Order Rosales. 494 

Flowers monoecious or dioecious. Order Euphorbiales. 690 

Trees or shrubs : flowers monoecious or dioecious, or polygamous. 

Leaves represented by appressed whorled scales : stems or branches loosely jointed. 

Order Casuarinales. 331 

Leaves not appressed scales : stems or branches not loosely jointed. 
Fruit 1-seeaed : seeds without tufts of hairs. 

Ovules 1 or 2 in each cavity of the ovary : flowers not in heads. 

Gynoecium 1-carpeIlary : stigma 1 : ovule laterally attached and amphitropous. 

Order Leitneriales. 336 
Gynoecium 2-carpellary : stigmas 2 : ovule erect and orthotropous or pendulous 

and anatropous. 
Pistillate flowers without a calyx : ovule erect and orthotropous. 

Order Myricales. 336 
Fistillate flowers with a calyx : ovule pendulous and anatropous. 
Leaf-blades simple. 

Fruit a nut or an achene. Corylaceae in Order Fagales. 343 

Fruit a drupe. Oleaceae in Order Oleales. 916 

Leaf-blades compound : fruit a samara. Oleaceae in Order Oleales. 916 

OvUles many : flowers aggregated into dense heads. Altingiaceae in Order Rosales. 494 

Fruit many-seeded : seeds each with a tuft of hairs. Order Salicales. 338 

Calyx present at least in the staminate or in the perfect flowers. 

Leaves represented by appressed whorled scales : branches loosely jointed. 

Order Casuarinales. 331 
Leaves not appressed scales : branches not loosely jointed. 

Flowers, at least the staminate, in aments, or ament-like spikes. 
Leaf-blades simple : ovule pendulous and anatropous. 

Pistillate flowers separate at maturity : fruit a nut or an achene. Order Fagales, 343 
Pistillate flowers forming aggregate fruits : fruit drupe-like. 

, , ^ . Artocarpaceae in Order Urticales. 355 

Leaf-blades pinnately compound : ovule erect and orthotropous. Order Juglandales. 332 
Flowers, at least the staminate, not in aments. 
a. Ovary superior. 

Gynoecium of 1 or several and distinct carpels : stigma and style solitary, 
• Carpel solitary. 

Style lateral and oblique. Petiveriaceae in Order Chenopodiales. 383 

Style axile, erect. 

Ovary neither enclosed nor seated in a hypanthium or a calyx-tube. 

Flowers not solitary in axils : land plants. 

Filaments free and distinct. Urticaceae in Order Urticales. 355 

Filaments adnate to the sepals or to the calyx-tube. 

^ Order Pkoteales. 817 

Flowers solitary in axils ; aquatic plants. 

^ Ceratophyllaceae in Order Ranales. 428 

Ovary enclosed in or seated in a hypanthium or a calyx-tube. 

Stamens borne under the gynoecium. 

AUioniaceae in Order Chenopodiales. 383 

Stamens borne on the hypanthium or adnate to the calyx-tube. 

Order Thymeleales. 818 
Carpels several : * . ' 

Stamens inserted below the ovary. Families in Order Ranales. 428 

Stamens inserted on the edge of a cup-shaped hypanthium. 

^ . ^ Rosaceae in Order Rosales. 494 

Gynoecium of 2 or several united carpels : stigmas or styles 2 or several. 
* Ovary, by abortion, 1-celled and 1-ovuled. 

Leaves with sheathing stipules (ocreae). Order Polygonales. 366 

Leaves stipulate, or if stipules are present they are not sheathing. 
Trees or shrubs. 

Anthers opening by slits : ovary not seated in a hypanthium. 

Ulmaceae in Order Urticalto. 355 
Anthers opening by hinged valves : ovary seated in an accrescent hypan- 
thium. Lauraceae in Order Thymeleales. 818 
Herbs or vines. 

t Leaves with stipules. 

Stipules herbaceous : inflorescence spicate or racemose : leaf-blades 

palmately veined. Cannabinacea^ in Order Urticales. 355 



KEY TO THE ORDERS ix 



^ 



Stipules scarious or hyaline : inflorescence cymose : leaf-blades pin- 

nately veined. Families in Order Chenopodiales. 383 

tt Leaves without stipules. 

Stigmas entire. Order Chenopodiales. 3S3 

Stigmas 2-cleft. Euphorbiaceae in Order Euphobbiales. 690 

** Ovary several-celled, or with several placentae, several-ovuled. 

Stai^ens hypogy nous, inserted under the gynoecium in the perfect flowers, not 
on a disk in the instillate flowers. 
Herbs. 

Flowers perfect. 

Ovary several-celled. 

Fruit baccate or nut-like, or a circumscissile capsule, the carpels 

terminal on the receptacle. Families in Order Chenopodiales. 383 
Fruit of several carpels, lateral on the receptacle, each carpel cir- 
cumscissile. Penthoraceae in Order Rosales. 494 
Ovary 1-2-celled. 

Stamens not tetradynamous, 4-8 : ovary l-celled. 

Order Chenopodiales. 333 

Stamens tetradynamous : ovary 2-celled. 

Brassicaceae in Order Papavekales. 460 

Flowers monoecious or dioecious. 

Ovules with the raphe towards the axis of the gymoecium. 

Euphorbiaceae in Order Euphorbiales. 690 

Ovules with the raphe away from the axis of the gynoecium. 

Buxaceae In Order Sapindales. 723 
Trees or shrubs, 

Gynoecium 5-carpellary, the carpels nearly distinct. 

Buettneriaceae in Order Malvales. 759 
Gynoecium 2-4-carpellary, the carpels united. 
Ovary 4-celled : fleshy maritime shrubs. 

Batidaceae in Order Chenopodiales. 383 
Ovary 2-celled : plants not fleshy. Oleaceae in Order Oleales. 916 

Stamens perigynous or epigynous, inserted on the^margin of a hypanthium or 
a disk. 

Fruit a samara. Families in Order Sapindales. 723 

Fruit not a samara. 

Fruit drupe-like or berry-like : shrubs or trees. Order Rhamnales. 747 

Fruit a capsule,: herbs. Order Aristolochiales. 1130 

b. Ovary inferior. 

Flowers not in involucrate heads. 

Fruit 3-winged, splitting into 3 nutlets. Gouania in Order Rhamnales. 747 

Fruit neither 3-winged nor splitting into carpels. 
Fruit a berry or a drupe, or nut-like. 

Calyx deciduous as a lid : stamens numerous. 

ChytracuUa in Order Myktales. 822 
Calyx of valvate or imbricated sepals : stamens few. 

Stamens as many^as the perianth-members and alternate with them, or 
fewer. 
Herbs, with succulent steins and leaves, or woody below : flowers 

perfect. Tetragoniaceae in Order Chenopodiales. 383 

Trees or shrubs : flowers dioecious. Nyssaceae in Order Ammiales. 851 
Stamens as many as the perianth-members and opposite them, or twice 
as many. 

Styles present. 

Ovules mostly on basal placentae, sometimes pendulous : cotyle- 
dons not convolute : tree or root-parasites. Order Santalales. 1101 
Ovules not on basal placentae : cotyledons convolute : not parasitic 

plants. Families in Order Myrtales. 822 

Styles wanting : stigmas sessile. Gunneraceae in Order Myrtales. 822 

Fruit a capsule. 

Sepals as many as the ovary-cavities or one-half as many. 

Calyx regular and the sepals half as manv as the cavities in the ovary, 

or irregular. Order Aristolochiales. 1130 

Calyx regular and the sepals as many as the cavities in the ovary. 

Order Myrtales. 822 

Sepals (4-^) at least twice as many as the ovary-cavities (2). 

Saxifragaceae in Order Rosales. 494 

Flowers, at least the staminate, in involucrate heads. 

\ Ambroslaceae In Order Carduales. 1148 

B. Corolla present. 

* Petals distinct, at least at the base. 

Carpels solitary, or several and distinct, or united only at the base. 

Stamens at the base of the receptacle, L e., hypogynous. . ^ ^ t. a^4 

Flowers in monoecious heads. Platanaceae in Order Rosales. 494 

Flowers not in monoecious heads. ^ , t> -«« 

Plants with relatively firm stems and leaves, not succulent. Order Ranales. 428 

Plants with succulent stems and leaves. Sedaceae in Order Rosales. 4W 

Stamens on the margin of a hypanthium (the hypanthium very small In some Saxifra- 

Pllms without secreting glands in'the bark, , Order Rosales. 494 

Plants with secreting glands in the bark. Sunanaceae in Order Geraniales. 658 

Carpels several and united. 

t Ovary superior. . ^ _ 

t Stamens inserted at the base of the ovary or receptacle. 

g Stamens numerous. 
Sepals imbricated. 
Calyx deciduous. 



Order Papaverales. 460 



X KEY TO THE ORDERS 



Calyx persistent. 

Stigmas pinnatifid : insectivorous plants. 

Dionaeaceae in Order Sarraceniales. 491 

Stigmas not pinnatifid : plants not insectivorous (except in Sarraceniales). 
Styles or stigmas distinct or united, but not discoid. 
Leaves glandular or pellucid-punctate. 

Placentae axile. Rutaceae in Order Geraniales. 658 

Placentae parietal. Canellaceae in Order Hypericales. 781 

Leaves not glandular. 

Placentae pariental : gynoeclum vnih a 1-celled ovary. 
Anther-sacs opening lengthwise. 

Capparidaceae in Order Papaverales. 459 

Anther-sacs opening at the top. 

Bixaceae in Order Hypericales. 781 

Placentae axile or central : gynoecium with a 2-several -celled ovary, 

for with distinct carpels.) Theaceae in Order Hypericales. 781 
Styles or stigmas united into a disk. 
Herbs : bog or aquatic plants. 

Petals and sepals numerous : leaves with flat blades : aquatic plants. 

Nymphaeaceae in Order Ranales. 428 
Petals and sepals few : leaves with pitcher-like organs : bog plants. 

Sarraceniaceae in Order Sarraceniales. 491 
Shrubs or trees : plants not aquatic. Clusiaceae in Order Hypericales. 781 
Sepals valvate. 

Stamens with distinct filaments. 

Ovary 1-celled : placentae parietal. Capparidaceae in Order Papaverales. 460 
Ovary 2-several-celled : placentae axile or central. 

Families in Order Malvales. 759 
Stamens with united filaments. Order Malvales. 759 

g Stamens few. not over twice as many as the petals. 
Stamens as many as the petals and opposite them. 

Anther-sacs opening by hinged valves. Podophyllaceae in Order Rakales. 428 
Anther-sacs opening by slits. 

Flowers monoecious. Euphorbiaceae in Order Elthorbiales. 690 

Flowers perfect. 

Ovules, or seeds, several or many : embryo coiled. 

Portulacaceae in Order Chenopodiales. 383 
Ovules, or seeds, solitary : embryo straight. 

Plumbaginaceae in Order Primulales. 898 
Stamens as many as the petals and alternate with them, or more, sometimes 
twice as many. 
Stamens 6 : petals 4: sepals 2 or 4. Families in Order Papaverales. 460 

Stamens, petals and sepals of the same number, or stamens more, usually twice 
as many as the sepals or petals. 
Ovary 1-celled. 

Ovules, or seeds, on basal or central placentae. 

Herbs. Families in Order Chenopodiales. 383 

Trees or shrubs. 

Stamens with free and distinct filaments. 

Tamaricaceae in Order Hypericales. 781 
Stamens with partially united filaments, and usually adnate to the 

corolla. Styracaceae in Order Ebenales. 908 

Ovules, or seeds, on parietal placentae. 

Stigmas 2-cleft. 

Anther with an inconspicuous connective. 

Stigmas not brush-like. Droseraceae in Order Sarraceniales. 491 
Stigmas brush-like. Turneraceae in Order Hypericales. 781 

Anther with the conspicuous connective produced beyond the sacs. 

' . ' - Papayaceae in Order Passiflorales. 805 

Stigmas entire. 

Stamens with united filaments and no staminodia. 

Families in Order Malvales. 759 
Stamens with distinct filaments. 

Staminodia present. Parnassiaceae in Order Rosales. 494 

Staminodia wanting. Families in Order Hypericales. 781 

Ovary several-celled. 

Stamens adnate to the gynoecium. 

Asclepiadaceae in Order Asclepiadales. 933 
Stamens not adnate to the gynoecium. 

Stamens with wholly or partly united filaments. 

Anthers opening lengthwise. Families in Order Geraniales. 658 

Anthers opening by pores. Polygalaceae in Order Polygalales. 682 
Stamens with distinct filaments. 

Anthers opening by pores. Families in Order Ericales. 876 

Anthers opening by slits. 

Stigmas or styles distinct and cleft, or foliaceous, or united by 

pairs. Order Euphorbiales. 690 

Stigmas or styles all distinct or all united, neither cleft nor foli- 
aceous. 

Stamens 2, Oleaceae in Order Oleales. 916 

Stamens more than 2. 

Leaves with compound blades. , 

Families in Order Geraniales. 658 
Leaves with simple blades. 

Ovule solitary in each carpel. 

Styles distinct : ovule pendulous. 

Families in Order Geraniales. 658 



KEY TO THE ORDERS xi 



styles united : ovule erect or ascending. 

Limnanthaceae in Order Sapindales. 723 
Ovules 2 or more in each carpel. 

Flowers irregular : stamens united at the top or con- 

. verging. 

Placentae axile, 

Balsaminaceae in Order Geraniales. 658 
Placentae parietal. 

Violaceae in Order Hypericales. 781 
Flowers regular: stamens neither united nor con- 
verging at the top. 
Carpels not circumscissile at maturity. 
Placentae parietal. 

Cistaceae in Order Hypericales. 781 
Placentae axile or central. 
Styles distinct. 

Elatinaceae in Order Hypericales. 781 
Styles united. 

Ovary sessile : filaments filiform. 

Tiliaceae in Order Malvales. 759 
Ovary stipitate : filaments fusiform, 

Koeberliniaceae in Order Geraniales. 658 
Carpelscircumscissile at maturity. 

Penthoraceae in Order Rosales. 494 
XI Stamens inserted on the margin of a disk or hypanthium (perigynous or hypogynous). 
Stamens fewer than the sepals or the petals. 

Hippocrateaceae in Order Sapindales. 723 
Stamens as many as the sepals or the petals* or more. 

Stamens as many as the petals and opposite them. 

Styles and upper part of the ovaries distinct : ovules and seeds many, 

Saxifragaceae in Order Rosales. 494 
Styles united. 

Ovules and seeds numerous. Moringaceae in Order Papaverales. 459 

Ovules and seeds solitary or 2. Order Rhamnales. 747 

Stamens as many as the petals and alternate with them, or more or many. 

Styles distinct. 

Upper part of the ovaries distinct, at least at maturity. 

Saxifragaceae and Iteaceae in Order Rosales. 494 

Upper part of the ovaries united. Order Sapindales. 723 

Styles united. 

Hypanthium flat or obsolete : disk fleshy. 

Plants without secreting glands in the bark. Order Sapindales, 723 

Plants with secreting glands in the bark. Families in Order Geraniales. 658 

Hypanthium cup-shaped or campanulate : disk obsolete or inconspicuous 

Order Myetales. 822 
tt Ovary inferior. 

Stamens numerous. 

Styles and stigmas united into a disk : water-plants with endogenous stems. 

Nymphaeaceae in Order Rosales. 494 
Styles distinct, or united, but not forming a disk with radiating stigmas : land-plants 
with exogenous stems. 
Styles distinct. 

Stamens distinct : stigmas simple ; shrubs or trees. Families in Order Rosales. 494 
Stamens with united filaments : styles branched : herbs. Order Begoniales. 817 
Styles united. 

Shrubs or trees ; not succulents, sometimes woody vines. 
Hypanthium not produced beyond the ovary. 

Escalloniaceae in Order Rosales. 494 
Hypanthium produced beyond the ovary. Families in Order Myrtales, 822 
Herl^, or shrub-like or tree-like succulents. Order Opuntiales. 808 

Stamens not more than twice as many as the petals. 

Styles wanting: stigmas sessile. Gunneraceae in Order Myrtales. 822 

Styles present. 
Styles distinct. 

Ovules several in each cavity of the ovary : fruit a capsule or a fleshy many- 
seeded berry. 

Fruit, if dehiscent, valvate. Families in Order Rosales. 494 

Fruit circumscissile. Portulacaceae in Order Chenopodiales. 383 

Ovules solitary in each cavity of the ovary : fruit a drupe or 2-6 more or less 

united achenes. Order Ammiales, 851 

Styles united, or single. 
Plants without tendrils. 

Ovary enclosed in or surpassed by the hypanthium or adnate to it. 

Anther-sacs opening by pores. Vacciniaceae in Order Ericales. 876 

Anther-sacs opening by slits. 

Ovules solitary in each cavity of the ovary. Order Ammiales. 851 

Ovules several in each cavity. 

Ovary with parietal placentae. Loasaceae in Order Opuntiales. 808 
Ovary with central or basal placentae. 

Families in Order Myrtales. 822 
Ovary exceeding the hypanthium. the top free. 

Escalloniaceae in Order Rosales. 494 
Plants with tendrils. ^ ^ , , . . 

Herbs : fruit a pepo : leaf-blades palmately veined. 

Cucurbitaceae in Order Campanulales. 1134 
Shrubby vines : fruit drupaceous, separating into nutlets : leaf-blades pin- 

nately veined. Rhamnaceae in Order Rhamnales, 747 



Xll 



KEY TO THE ORDERS 



Families in Order Rosales. 494 



Fiimariaceae in Order Papaverales. 460 

Oxalidaceae in Order Geraniales. 658 

Order Polygalales. 682 

Families in Order Ericales. 87G 

Aquifoliaceae in Order Sapindales. 723 



Families in Order Ericales. 
Armeriaceae in Order Primulales. 



** Petals more or less united. 
Ovary superior. 

Stamens free from the corolla. 
Gvnoecium of a single carpel. 
Gynoecium of several united carpels. 
Filaments united. 

Stamens diadelphous. 
Stamens monadelphous. 

Anther-sacs opening by slits. 
Anther-sacs opening by pores. 

Calyx and corolla very irregular. 
Calyx and corolla regular. 

Filaments distinct. 

Styles wanting or very short : stigma sessile. 

Styles elongated. 

Ovary several-celled. 

Ovary l-celled. 
Stamens partiallv adnate to the corolla. 

Stamens as many as the lobes of the corolla and opposite them, or twice as many or more. 

Ovary l-celled. 

Placentae central or basal. * Order Primulales. 

Placentae parietal. Fouquieriaceae in Order Hypericales. 

Ovarv several-celled. 

Upper portion of the ovaries distinct. Sedaceae in Order Rosales. 

Upper portion of the ovaries united. Order Ebenales. 

Stamens as many as the lobes of the corolla and alternate with them, or fewer. 
Corolla not scarious, veiny : fruit various, but not a pyxis. 
Gynoecium of 3-6 carpels. 

Shrubs or trees: ovules and seeds few. Aquifoliaceae in Order Sapindales. 
Herbs, or creeping or tufted shrubby plants : ovules and seeds numerous. 
Stamens adnate up to the sinuses of the corolla : creeping evergreen under- 
shrubs. Diapensiaceae in Order Ericales. 

Stamens adnate to the lower part of the corolla-tube : vines. 

Families in Order Polemoniales. 

Gynoecium of 2 carpels. 

Carpels distinct, except sometimes at the apex. 

Style terminal. Order Asclepiadales. 

Style basal. Dichondraceae in Order Polemoniales. 

Carpels united. 

Ovary l-celled, with central placentae. Order Gentianales. 

Ovary 2-celled, or falsely 4-ceUed, or if l-celled with parietal placentae. 
Stamens 2 and opposite each other, or 3. Order Oleales. 

Stamens usually 4 or 5, if 2 by reduction not opposite each other. 
Leaves with stipules or stipular lines at their bases. 

Spigeliaceae in Order Gentianales. 
Leaves with no traces of stipules. Order Polemoniales. 

Corolla scarious, veinless : fruit a pyxis. Order Plantaginales. 

Ovary inferior. 

Stamens with the filaments free from the corolla. 

Stamens 10 : anther-sacs opening by terminal pores or chinks. 

Vacciniaceae in Order Ericales. 

Stamens 5 or fewer : anther-sacs opening by longitudinal slits. Order Campanulales. 
Stamens adnate to the corolla. 

Ovary with 2-many fertile cavities and 2-many ovules : calyx unmodified, at least not 
a pappus. 

Plants tendril-bearing. Cucurbitaceae in Order Campanulales. 

Plants not tendril-bearing. 

Ovules mostly on basal placentae : plants parasitic. Order Santalales. 

Ovules variously borne, but not on a basal placenta : plants not parasitic. 

Order Rubiales. 
Ovary with one fertile cavity. 

Ovules numerous on a basal placenta. Primulaceae in Order Primulales. 

Ovule solitary, the placentae not basal. 

Flowers not in heads, often in head-like spikes or racemes. Order Valerianales. 

Flowers in involucrate heads. Order Carduales. 



876 
898 



898 
781 

494 
908 



723: 



876 
955 



933 
956 

921 

916 



921 

956 

1097 



876 
1134 



1134 

1101 

1104 

898 

1127 
1148 



J 



\ 





OPvA 



OF THE 



SOUTHEASTERN UNITED STATES 



SuBKiNGDOM PTERIDOPHYTA.^ Ferns and Fern Allies. 

Plants containing woody and vascular tissues. They produce spores 
asexually, each of whic^i, on germination, develops into a prothallium 
(gametophyte). The prothallia bear the reproductive organs ; the female 
organ is known as an archegone, the male as an antherid. As a result of 
the fertilization of an egg in the archegone by a sperm produced in the 
antheridy the asexual state of the plant is developed (sporophyte) ; this 
phase is represented by a fern or an allied plant. 



Order 1. OPHIOGLOSSALES. 

Succulent plants, consisting of a stem and leaf growing from a fleshy root- 
stock. Sporophyll in the form of a spike or panicle, the sporanges formed from 
the interior tissues, naked, each opening at maturity by a transverse slit. Spores 
yellow, of one sort. Prothallia subterranean, devoid of chlorophyll. 

Family 1. OPHIOGLOSSAOEAE Presl. Adder' s-tongue Family. 
Characters of the order. 

Veins reticulated : sporanges cohering in one or more distichous spikes. 

Terrestrial: spike single, long-stalked. 1. Ophioglossum. 

Epiphytic on palmettos : spikes several, short-stalked, 2. Cheiroglossa. 

Veins free : sporanges distinct, borne in spikes or panicles. 3. Botrychium. 

1. OPHIOGLOSSUM L. 

Low terrestrial plants, with small rootstocks, and slender fleshy roots. Bud for the 
following year formed at the side of the base of the stem. Leaf solitary, borne on the 
stem : blade simple, entire. Sporophyll terminal, formed of two rows of large coalescent 
sporanges. Veins reticulated. Spores sulphur-yellow. Adder' s-tongue. 

Leaf-blades oyate or elliptic-oblong, 3-12 cm. long, with several equal or parallel veins at the base. 

Leaf-blades obtuse: areolae with few veinlets. . 1. O. vulgatum. 

Leaf-blades apiculate : areolae broad, with many veinlets. 2. 0. Engelmannii. 
Leaf-blades cuneate or cordate ar the base, with unequal veins at the base. 

Rootstocks slightly tuberous-thickened : leaf-blades lanceolate or ovate with 

a cuneate base. ' 3. 0. pttsillum. 

Rootstocks globose: leaf-blades ovate with a cordate base. 4. 0. crotalophoroides. 

1. Ophioglossum vulgatum L. Eootstock oblique. Stem slender, 1-4 dm, tall, 
simple, glabrous, bearing a leaf near its middle ; leaf-blade sessile, ovate or elliptic-oblong, 
3-12 cm. long, rather tirm in texture, distinctly reticulated, with few veinlets within the 
areolae ; basal veins 9-13 : spike solitary, 1-2.5 cm. long, erect apiculate. 

In moist meadows and thickets, Prince Edward Island to Alaska, south to Florida. Also in Europe 
and Asia. May to August. 



^ Contributed by Prof. Lucien Marcus Underwood. 



2 OPIIIOGLOSSACEAE 

2. Ophioglossum EngelmAnnil Prantl. Eootstock cylindric. Stem 8-22 cm. high. 
bearing a leaf; blade elliptic or lanceolate-elliptic, 3-9 cm. long, sharply apiculate, fleshy 
but becoming pellucid ; basal veins 13 or more, the transverse vehilets oblique, forming 
broad oblong-hexagonal areolae with numerous veinlets : spike 1.5-2.5 cm. long, apiculate. 

In moist grounds, Virginia to Indiana, Missouri. Texas and Arizona. 

3. Ophioglossum pusillum Nutt. Kootstock slightly thickened. Stem slender, 
2.5-4 cm. high, bearing a leaf near the base ; blade lanceolate or ovate with a cuneatebase ; 
basal veins 3, the midvein branching by lateral veinlets which form narrow areolae with no 
free veinlets : spikes 6-12 mm. long, with 6-14 sporanges on either side. [0. nudkaide 
Chapm., not L. f.] 

In sandy soil, Georgia to Florida and Louisiana. 

4. Ophioglossum crotalophoroides Walt. Eootstock globose. ^ Stem relatively 
stout, bearing one leaf ; blade concave, broadly ovate, 8-30 mm. long, with a cordate base 
and acute apex ; basal veins 5, the midvein rarely branched, the lateral veins freely anas- 
tomosing, forming short hexagonal areolae with rarely a free veinlet : spikes broad, 4-12 
mm. long, with 4-lltsporanges on either side. 

In sandy soil, South Carolina to Florida and Texas, Also in tropical America. 

2. CHEIROGLOSSA Presl. 

Epiphytic plants, with slender fleshy roots. Leaf-bladessimple, palmately lobed, bear- 
ing several spikes near their bases. Veins reticulated ; the areolae without free veinlets. 

1. Cheiroglossa palm^ta (L. ) Presl. Kootstock tuberous, covered with fine woolly 
chaff. Leaves fleshy ; blades 10-25 cm. long, on a stem nearly as long, palmately divided 
into 2-9 broadly spreading lobes, or rarely entire and lanceolate : spikes 2-16, or rarely 1, 
short-stalked, 2.5 cm. long or more. {^Ophioglossum palmatum L.] 

On palmettos, Florida and tropical America. 

3. BOTRYCHIUM Sw. 

Fleshy plants, with erect rootstocks, and clustered fleshy roots, the bud for the succeed- 
ing year imbedded in the base of the stem. Leaf-blade pinnately or ternately divided, or 
compound. Sporophyll pinnate or 3-pinnate, with sessile distinct sporanges in rows on 
either side of its branches, forming large panicles in some species. Veins free. Spores 
yellow. MooxwoRT. 

Bud for the following rear enclosed in the base of the stem : leaf-blades ternate or biternate. attached 
near the base of the common stem. 

Leaf-blades sessile or nearly so : spores maturing in early spring. 1. B, biiernatum. 
Leaf-blades stalked : spores maturing in fall. 

Leaf-blade biternate, thin. 2. B. tenuijolium. 

Leaf-blade ternate, with bipinnate or tripinnate divisions, fleshv. 3. B. obliquum. 
Bud enclosed in a cavity at one side of the base of the stem: leaf-blades ternate, 

decompound, sessile at the middle of the stem. 4. B, Vnginianum. 

1. Botrychium bitemitum (Lam.) Underw. Plant 6-10 cm. high, bearing a single 
leaf ; blade sessile or nearly so, ternately compound, 8-10 cm. wide, 5 cm. long, with the 
middle division slightly larger than the lateral ones and like them nearly 3-pinnate ; ulti- 
mate segments somewhat lunate, usually 5-6 mm. wide, the outer margin crenate, the 
lateral margins decurrent on the rachis : sporophyll on a stalk 8 cm. long or longer, 2- 
pinnate : bud smooth or slightly pilose. 

On dry grassy knolls. South Carolina to Louisiana. The spores mature in March or ApriL 



2. Botrychium tenuifolium Underw. A slender plant Avith a biternate leaf-blade. 




wide, thin, sharply serrate, or nearly 2- or 3-incised ; petiole 3-6.5 cm. long, very slender; 
panicle 3-6 cm. long, bipinnate or basely tripinnate below on a slender stalk, 6-22 cm. long. 

In low grounds, Alabama, Florida and Louisiana. The spores mature in fall. 

3. Botrychium obliquum Muhl. Plant robust, 1.5-5 dm. high. Leaf rising from 
near the base of the stem on a stalk 2-10 cm. long, or more ; blade ternate, with the three 
divisions nearly equal, 2-pinnate or somewhat 3-pinnatifid in larger forms, the ultimate 
segments obliquely ovate or oblong-lanceolate, the terminal one of each division elongated, 
1-2 cm. long, the margins crenate or serrate: sporophyll long-stalked, 3-4-pinnate : bud 
densely pilose, both portions bent in vernation. ^B. ternatum Chapm., not Sw.] 

In low woods and open places from New Brunswick to Minnesota, south to Florida and Mexico. 
The spores mature from August to October. 



OSMUNDACEAE 



3 



4. Botrychium Virginiinum (L.) S\v. Plant 2-6 dm. high, the stem slender but 

fleshy. Leaf-blade nearly or quite sessile above the middle of the stem, spreading, thin, 
ternate with the primary divisions pinnate or 2-pinnate and the segments 1-2-pinnatifid; 
ultimate segments oblong, more or less toothed near the apex ; epidermal cells flexuous : 
sporopliyll long-stalked, 2-3-pinnate : bud for the following year pilose, enclosed in a 
glabrous cavity at one side of the lower part of the stem : sporophyll recurved its whole 
length, the leaf reclined upon it in vernation. 

In woods. Nova Scotia to British Columbia, Florida and Arizona. Also in Europe and Asia. Spring 

Order 2. FILICALES. 

Terrestrial aquatic or epiphytic plants, various in habit. Sporanges devel- 
oped from the epidermal tissues, on the back or margin of the leaf-blades, or in 
panicles formed from modified leaves. Spores of one sort. Prothallia with 
chlorophyll, flat, terrestrial. 

Leaves with filmy translucent blades : sporanges sessile on a filiform receptacle. 

-Fam. 1, Hymenophyllaceae. 
Leaves with herbaceous or leathery blades : sporanges on normal or 
modified leaf-blades. 
Sporanges in panicles or spikes, 

Sporanges nearly globose, with a rudimentary ring. Fam. 2. Osmundaceae. 

Sporanges ovoid or pyriform, with a complete apical ring. Fam. 3. Schizaeaceae. 

Sporanges borne on the back or margin of a leaf-blade. 

Sporanges scattered, globose, with a more or less complete broad 

ring, opening vertically ; aquatic. Fam. 4. Ceratopteridaceae. 

Sporanges arranged in sori, with a complete ring, opening trans- 
versely : terrestrial or epiphytic. Fam. 5. Polypodiaceae. 

Family 1. HYMENOPHYLLACEAE Gaud. Filmy Fern Family. 

Membranous, mostly small ferns with filiform or slender creeping or hori- 
zontal rootstocks. Leaf-blades usually much divided. Sporanges sessile on a 
filiform usually elongated receptaclCj surrounded by a transverse ring which 
opens vertically. 

1. TRICHOMANES L. 

Delicate filmy plants. Leaves usually with much divided blades. Receptacle slender- 
filiform, surrounded by a tubular or funnel-shaped indusium which is truncate or slightly 
2-lipped. 

Leaf-blades entire or sli^^tly pimiatifid, &-2-4 mm. long. 1. T. PeiersiL 

Leaf-blades 2-3-pinnatiiid, 8-27 cm. long, 2. T, Boachianum. 

1. Tricbomanes Petfersii A. Gray. Eootstocks widely creeping. Leaves with a 
few black hairs along the margins when young ; blades entire, or slightly pinnatifid, 6-24 
mm. long, 2-4 mm. wide, on a stalk 2-4 mm. long : indusium solitary, terminal, funnel- 
form, expanded and slightly 2-lipped at the mouth : receptacle mostly included. 

Under moist rocks, AVinston and Etowah Counties, Alabama, and in Georgia and Mississippi. 

2. Trichomanes Boschiclnum Sturm. Rootstocks wiry, tomentose. Leaves erect or 
ascending; petioles 2.5-7.5 cm. long, naked or nearly so ; blades 5-20 cm. long, 1.5-3.3 
cm. wide, lanceolate or ovate-lanceolate, 2-3-pinnatifid : leaflets ovate, obtuse, the upper 



side of the cuneate base parallel or appressed to the narrowly winged rachis ; segments 
toothed or cut into linear divisions : indusia terminal on short lobes, 1-4 on a segment, 



slightly 2-lipped at the mouth : receptacle partially exserted. [T. rctdicaris A. Gray, not Sw.] 
On wet rocks, Kentucky to Alabama and Florida. Also widely distributed in the tropics. 

Family 2. OSMUNDACEAE R. Br. Cinnamon Fern Family. 

Large plants, with stout often erect rootstocks. Leaves coiled in vernation : 
blades 1-2 pinnate : veins free, mostly forked, running to the margins of the 
leaflets or lobes, Sporanges large, globose, with no ring or mere traces of a 
transverse ring of thick-Avalled cells, borne on modified contracted leaflets, or in 
clusters (sori) on the lower surface of the leaflets. 

1. OSMUNDA L. 

^ 

Swamp plants, growing in large crowns, with the fertile (spore-bearing) portions very 
much contracted, the short-pedicelled naked sporanges on the margins of their rachisdike 



4 



SCHIZAEACEAE 



divisions, which are destitute of chlorophylh Veins forked, regular and prominent. 
Sporanges each opening by a longitudinal cleft into two halves. Spores green. 



Leaf-blades 2-pinnate, fertile at the apex. 

Leaf-blades 2-pinnatifid, wholly or partially fertile, or sterile. 

Leaflets of sterile leaf with a tuft of tomentum at the base ; fertile leaf normally 
distinct from sterile. • 

Leaflets of sterile leaf without a tuft of tomentum at the base; leaves fertile in 

the middle. 



1. 0. sjyedabiUs, 



2. 0, cinnamomea. 

3. 0. Claytoniana, 



1. Osmunda spectdbilis Willd. Leaves several, clustered, 6-20 dm. high ; blades 
2-pinnate. Leaflets 1.5-3 dm. long, 5-10 cm. wide, their segments oblong-ovate, or lance- 
olate-oblong, sessile or slightly stalked, glabrous, finely serrulate, especially near the apex 
and occasionally crenate towards the truncate oblique or cordate base : sporophylls linear- 
cylindric, panicled, withering and shrivelling with age, greenish before maturity, but 
becoming dark-brown after the spores have fallen. 

In swamps and marshes, New Brunswick to Nebraska, Florida and Mississippi. Also in Mexico. 
Distinct from the European O. regalis L. May-July. Royal Fekn. 

2. Osmunda cinnamomea L. Eootstock widely creeping, bearing a cluster of 
sterile leaves with one or several fertile ones within. Leaves erect or nearly so ; petioles 3 
dm. long, or longer, clothed with ferruginous tomentum when young, glabrous when old ; 
blades 3-12 dm. long, with merely a tuft of tomentum at the base of each leaflet ; leaflets 
linear-lanceolate, deeply pinnatifid into oblong obtuse segments : sporophyll 2-pinnate, con- 
tracted, soon withering: sporanges cinnamon-colored after the numerous green spores have 
been discharged. 

In wet places, Nova Scotia to Minnesota, south to Florida and Mexico. May-June. Cinnamon 
Fern.— Forms occur with leaves variously intermediate between the sterile and fertile. 

3. Osmunda Claytoniina L. Eootstock bearing a cluster of ascending or arching 
leaves, some usually partially fertile and taller than the sterile- Leaves 6-20 dm. long, 
1.5-2.5 dm. wide; blades 2-pinnatifid ; sterile leaflets linear-lanceolate, without tufts of 
tomentum at the base, deeply cleft into oblong obtuse segments ; some of the leaf-blades 
contracted at the middle and bearing 2-6 pairs of sporophylls with dense cylindric divi- 
sions greenish at first, afterward dark-brown. 

In moist or shaded places, Newfoundland to Minnesota, North Carolina and Missouri. May-July. 

Family 3. SCHIZAEACEAE Keichenb. Curly-grass Family. 

Plants various in habit, with simple or pinnate leaf-blades. Sporanges 
borne in spikes or panicles, sessile, each provided with an apical ring opening 
vertically by a longitudinal slit. 

Twining : sporanges in ample panicles in the upper portion of the leaf : leaflets palmate. 

_ . . ; , 1- Lygodium. 

Erect : sporanges in panicles borne on the elongated lower leaflets. 2. Ornithofteris. 

1. LYGODIUM Sw. 

Twining or climbing plants. Leaves with the lower divisions sterile, variously 
stalked and lobed, the fertile divisions terminal, panicled. Sporanges ovoid, solitary or 
in twos, in the axils of imbricated scale-like indusia. Indusia fixed by their broad bases 
to short oblique veinlets. 

1. Lygodium palm^tum (Bernh.) Sw. Eootstock slender, horizontal. Leaves 
ample ; petioles slender, flexible and twining; blades 4-10 dm. long, their short alternate 
branches 2-forked, each fork bearing a nearly orbicular 4-7-lobed leaflet, which is more or 
less cordate at the base with a narrow sinus ; 'surfaces naked ; fertile leaflets contracted, 
several times forked, forming terminal panicles : sporanges solitary. 

^ JP °??^^^ thickets and open woods. New Hampshire and Massachusetts, to Pennsylvania, Tennessee 
and Florida ; rare or local. Summer. Climbing Fern. 



2. ORNITHOFTERIS 



Erect plants, with creeping or horizontal rootstocks. Leaves with the lower pair of 
leaflets elongated and often overtopping the blade, bearing numerous panicles of sporanges 



which are borne in two rows on the back of very narrow divisions. Veins free. [Anemia Sw.] 



Leaf-blades simply pinnate. 
Leaf-blades pinnately decompound. 

1. Ornithopteris Mealc^na 



1. 0. Mexicana, 

2. O. adiantifolia. 

1 

(Kl.) Underw. Leaf-blades 2-4 dm. long, on petioles 
of e(iual length, with a large terminal leaflet and from 4-6 pairs of lateral ones ; leaflets 



I 



POLYPODIACEAE 



5 



Omithopti 



ovate-lanceolate, short-stalked, some-what leathery, smooth and manifestly flossy ; midrib 
distinct, with oblique parallel veins: sporopliylls long-stalked, overtopping the leaf. 

In dry soil, western and southern Texas and adjacent Mexico. 

Leaf-blades triangular-ovate, 12-20 cm. 
long, on usually elongated petioles, slightly pubescent, ^pinnately decompound ; ultimate 
segments obovate or cuneate, entire or lobed, striate above with numerous flabellate veins. 

In sandy soil or coral rock, peninsular Florida. Also in the West Indies and Mexico. 

Family 4. CERATOPTERIDACEAE Underw. Floating Fern Family. 

Aquatic succulent plants, floating, or rooting in the mud. Leaves of two 
kinds, some with flat blades, the sporophylls narrow^ed, with broadly reflexed 
margins meeting at the midrib. Sporanges scattered, sessile, each with a broad 
complete partial or obsolete ring. Sori seated on two or three veins that run down 
the length of the leaf-blade, nearly parallel to both the edge and the midrib. 

1. CERATOPTERIS Brongn. 

Characters of the family. Floating Fern. 

1. Ceratopteris thalictroides (L. ) Brongn, Leaves tufted ; petioles inflated, filled 
with large air-cavities ; blades floating, 15-35 cm. long, simple or only slightly divided 
when young, 2-pinnate at maturity : sporophylls 2-3-pinnate, erect or ascending, the ulti- 
mate segments pod-like. 

In deep or shallow water, peninsular Florida and Louisiana. Also widely distributed in the tropics. 

Family 5. POLYPODIACEAE R. Br. Fern Family. 

Plants various in habit. Rootstocks creeping or horizontal, elongated, or 
short and erect. Leaves various, coiled in vernation : blades entire, pinnate, 
pinnatifid or decompound. Sporanges borne in clusters (sori) on the lower side 
or margins of the leaf-blades, stalked, provided with a vertical ring, open trans- 
versely. Sori frequently with a membranous covering (indusium), Prothallia 
green. 

a. Spqriferous leaf-blades flat, or their edges merely revolute. 
Sori without indusia. 

Sori covering the leaf-Llades or portions of them with a uniform layer. 1. AcrosticHum, 

Sori more or less separated from each other. 

Sori roundish, not more than twice as long as broad. 

Leaves with petioles jointed to the rootstocks; blades entire, pin- 
natifid or 1-pinnate. 
Veins free ; leaf-blades (In our species) pinnatifid or pinnate. 2. Polypodium, 

Veins copiously anastomosing. 

Veins forming regular ample areolae : leaf-blades pinnatifid. 3. Phlkbodium. 
Veins, or those parallel to the margins, forming irregular areo- 
lae : leaf-blades simple. 
Leaves ample : veins parallel to the margins with interven- 
ing finer areolae. 
Leaves relatively small: veins with irregular areolae through- 
out. 
Leaves not jointed to the rootstocks : blades (in our species) 2-3-pin- 

natifid or ternate. 

Veins free. 

Veins connivent, the branches of contiguous groups uniting to form 

one or more arches. 

Sori linear. 

Leaf-blades simple. 

Leaves with very narrow grass-like blades: veins indistinct. 6. Vittaria, 

* Leaves with expanded blades : veins markedly anastomosing. 7. Cheilogramma. 

Leaf-blades 1-4-pinnate: sori marginal. 13. Notholaena. 

Sori with indusia. 

Indusia formed of the partially altered margin of the leaf-blade. 

Sporanges at the ends of veins, borne in a reflexed portion of the leaf- 
blade. 
Sporanges borne on a continuous vein-like receptacle connecting the 

apices of the veins. 
Indusia single, formed of the altered leaf-marprfn. 8. Pteris. 

Indusia double, a membranous one arising within the receptacle. . 9. Pteridium. 
Sporanges at the apices of unconnected veins or near them. 

Sori mostly forming a continuous indusium around the leaf-segments. 11. Pellaea. 

Sori minute; indusium usually interrupted, if continuous, leaf-seg- 
ments small and bead-like. 



4. Camfyloneuron. 

5. Phymatodes. 



25, Phegopteris. 

26. goniopteris. 



10. Adiamum. 



12. Cheilanthes. 



Indusia specially developed, not from the leaf-marpins: » 
Sori linear or oblong : indusia more than twice as long 



sori dorsal, 
as broad. 



f^jL '^^- . 



6 



POLYPODIACEAE 



29. FiLlx. 



Sori parallelto the midrib or rachis. Prr^rTrvT^M 

Veins free : sori continuous or nearly so. -t^- lij.ttii.NL.n. 

Veins anastomosing : sori interrupted, chain-like. Avr^TTi^TVi 

Leaves uniform : veins free between the son and the margin. lo. anchistea. 
Leaves dimorphous: veins everywhere anastomosing. 19. Lorinseria. 

Sori wholly or partially oblique to the midrib. 
Veins free : sori all oblique, 

Sori single on the upper side of a veinlet or rarely crossing it : 

leaf-blades (in our species) not entire. . IG. Asplexum. 

Sori continent in pairs with an apparently double indusium 

opening in the middle : leaf-blades entire. 1' • Fhyllitis. 

Veins united : sori partly parallel to the midrib, partly oblique. 18. Camptosorus. 
Sori orbicular or nearly orbicular : indusia less than twice as long as 

broad. 

a. Indusia superior. 

Sori mostly on the back of the veins. 

Indusia orbicular^ peltate, fixed by the center. 

Veins copiously united, forming areolae. 21. Tectaria. 

Veins free. 22. Polystichum 

Indusia reniform, or orbicular with a narrow sinus. 23. Dryoptekis. 

Sori at the ends of free veins : indusia reniform, opening toward 

the margin of the leaflet. 27. Nephrolepis 

b. Indusia wholly or partly inferior. 
Indusia partly inferior, delicate, fixed by a broad base, enclosing 

the sorus like a hood. 
Indusia whollv inferior, various in shape. ^ 

Indusia cup-shaped or somewhat 2-valved. 28. Dexnstaedtia. 

Indusia nearly orbicular or stellate. 30. Woodsia. 

B. Sporiferous leaf-blades closelv rolled together; segments necklace-like. 

Leaf-blades with anastomosing veins : rootstock horizontal. 20. Onoclea. 

Leaf-blades with free veins : rootstock stout, erect. 24. Matteuccia. 

w 

1. ACROSTICHUM L. 

Swamp-inhabiting plants, with the leaves growing in crowns. Sporanges spread over 
the whole lower surface of the leaf-blades, or of the upper leaflets. Veins forming copious 
areolae without free veinlets. 

Sporanges formed on the upper leaflets only. 1. A. aureum, 

Sporanges formed on all the leaflets of some leaves. 2. A, lomarioides. 

1. Acrostlchum aureum L. Eootstocks erect, solitary, or in masses. Petioles 
tufted, erect, woody, 1-7 dm. long, flattish, channeled, with two or three alternate pairs 
of black indurated spurs ; blades stiff, leathery, glossy, light green, 10-12 dm, long, 3-4 
dm. wide ; leaflets 12 pairs or more, rather distant : sporanges confined to the upper half 
or third of the leaf-blade : venation fine, oblique to the margin. 

Southern peninsular Florida. Also in tropical regions. 

2. Acrostichum lomarioides Jenman. Rootstocks similar to those of A, aureum. 
Petioles tufted, erect, somewhat fleshy, 4-7 dm. long, longitudinally ribbed, slightly an- 
gular ; blades erect-spreading, 10-12 dm. high, 3-6 dm. wide, slightly reduced at the base, 
abruptly reduced at the apex ; leaflets spreading, close or crowded, 25-30 pairs, the face 
turned upward and transverse to the rachis : sporanges covering all the leaflets of fertile 
leaves : areolae very fine, directed toward the margin. 



Southern peninsular Florida. Also in the West Indies, 



2. POLYPODIUM L. « ' 

Plants with creeping or horizontal rootstocks. Leaves various : petioles jointed to the 
rootstocks : blades pinnate or simple. Sori hemispheric, dorsal, in one or more rows on 
either side of the midrib, Indusium none. Veins free or only casually anastomosing. 

Both surfaces of leaf-blades naked, 

Sori large (2 mm. broad): lower segments of the leaf-blade scarcely smaller than the upper. 

. ■ 1. P. vulgare. 

Son smaller (1 mm, wide or less): lower segments of the leaf-blades reduced. 

Leaf-blades with segments 3 mm. wide or less : veins once forl^ed. 2. P. Plumula. 

Leaf-blades with segments 5 mm. wide or more : veins 2-3-forked. 3. P. pedinatam, 

under surface of leaf-blades with scattered peltate scales. 4, P. pohjpodioldes, 

1. Polypodium vulgcire L. Rootstocks widely creeping, densely covered with cinna- 
mon-colored scales. Leaves evergreen ; petioles light-colored, glabrous, 5-15 cm. long ; 
blades^vate-oblong or narrowly oblong in outline, slightly leathery, glabrous on both sur- 
faces, 7-25 cm. long, cut nearly to the rachis into linear or linear-oblong segments : sori 
borne about midway between the midrib and the margins of the segments. 

On rocks or rocky banks, or rarely on trees, almost throughout eastern North America. Also in 
Asia and Europe, Polypody. 



:^,riy- - 



POLYPODIACEAE 



7 



2. Polypodium Plumula II.B.K. Leaves erect or spreading; petioles 2.5-10 cm. 
long, black, slender ; blades narrowly lanceolate, 20-40 cm. long ; segments nnmerous, 
narrow, entire, blunt, the lower abruptly smaller, the surfaces naked except the black wiry 
rachis : veins once forked, obscure. 

Peninsular Florida. Also in tropical regions. 

3. Polypodium pectln^tum L. Leaves spreading or arching ; petioles rigid, 5-15 
cm. long; blades elliptic-lanceolate, 3-8 dm. long, cut to the rachis into horizontal entire 
or slightly toothed segments, the lower ones gradually reduced to triangular lobes : rachis 
naked or finely villous ; veins pellucid, twice or three times forked : sori of medium 
size in long rows. 

Eastern peninsular Florida. Also in tropical regions. 

4. Polypodium polypodioides (L. ) A. S. Hitchcock. Rootstocks woody, widely 
creeping. Leaves evergreen; petioles densely scaly, 2.5-4.5 cm. long; blades obloi)g 
or oblong-lanceolate, 3-15 cm. long, acute, cut very nearly or quite to the rachis into 
entire oblong or linear obtuse segments, nearly glabrous on the upper surface, the lower sur- 
face and rachis covered with gray peltate scales with darker centers : veins obscure. [/*. 
incanum Sw.] 

On trees or rocks, Pennsylvania to Illinois and Missouri, south to Florida and Texas. Also through- 
out tropical America. 

3. PHLEBODIUM R. Br. 

Tropical mostly epiphytic plants, with pinnate leaf-blades. Soi'i round, naked, dorsal, 

borne on the united ends of two or more free veinlets which are included in the ample 

areolae formed by the regular anastomosing veins. 

1. Phlebodium aureum (L. ) R. Br. Rootstock short, densely scaly. Leaves ample, 
3-6 dm. long ; petioles chestnut-colored, naked ; blades 6-15 dm. long, cut nearly to the 
rachis into broad entire or undulate segments : areolae copious. \_Polypodium aureum L.] 

On Sabal Palmetto, peninsular Florida. Also in tropical America. 

4. CAMPYLONEURON Presl. 

Tropical plants with usually simple and entire leaf-blades. Sori round, naked, dorsal, 
in one or two rows on either side of the midrib. Primary veins distinct from the midrib 
to the margin, connected by parallel transverse veinlets forming regular arches. Areolae 
similar, Avith two or more large sori. 

i. Camplyoneuron Phyllitidis (L. ^ Presl. Rootstocks stout, scaly. Leaves erect 
or arching; petioles short or wanting; blades simple, 3-9 dm. long, 2.5-10 cm. wide, 
leathery, acute, gradually narrowed below : areolae in rows of 6-12 from the midrib to the 
margin, [^Polypodium Phyllitidis L.] 

Southern peninsular Florida. Also in tropical America. 

5- PHYMATODES Presl. 

Tropical plants, often epiphytic, with simple leaf-blades. Sori rounded, naked, dor- 
sal, various in position. Veins forming fine copious irregular areolae with free veinlets 
spreading in various directions. 

1. Phymatodes exiguum (Hew.) Underw. Rootstocks widely creeping, slender, 
covered with linear ferruginous scales. Leaves elongated ; petioles 6-12 mm. long, 
slender, naked ; blades simple, 5-10 cm. long, entire, undulate or barely lobed, gradually 
narrowed to both ends : son in one series on free veinlets. [Polypodium Swartzii Baker.] 

Climbing on shrubs, Key Largo, Florida. Also in tropical America. 

ft 

6. VITTARIA J. E. Smith. 

Tufted often epiphytic plants, with grass-like leaves. Sori linear, continuous in 2- 
lipped marginal grooves or intramarginal lines, with the unaltered edge of the leaf-blade 
produced beyond, and often rolled over them, but without special indusia. Veins obscure 
l)ut forming a single row of areolae. 

1. Vittaria line^ta (L. ) J. E. Smith. Leaves 1.5-9 dm. long, 2-10 mm. wide, nar- 
rowed gradually toward a stout compressed stem, the edges often reflexed : sori in a broad 
intramarginal line in a slight furrow, the edge of the leaf-blade at first wrapped over it. 

On palmettos, middle and peninsular Florida. Also in tropical America. Grass Fekn. 



8 



POLYPODIACEAE 



7. CHEIIjOGRAMMA Blume. 

Epiphytes, relatively small, with simple leaf-blades. Sori linear, but the lines some- 
times interniptedj nearly marginal. Veins reticulated. 

1. Cheilogramma lanceol^tum ( L. ) Bhime. Eootstocks creeping. Leaves numer- 
ous ; petioles 2.5-5 cm. long ; blades simple, 15-32 cm. long, 12-16 mm. wide, entire, often 
somewhat crisped, tapering both ways, with prominent midrib and obscure immersed 
veins ; veins anastomosing, the outer ones free and enlarged at their apices : sori antemar- 
ginal in a mostly continuous line near the apex, [l^amitis hnceoktia (L. ) K. Br.] 

On trees, Old Ehodes Key, Florida. Also in tropical America. 

8. PTERIS L. 

Relatively large plants, with petioles continuous with the rootstock and variously di- 
vided leaf-blades. Sori marginal, linear, continuous, occupying a slender or filiform re- 
ceptacle, connecting the tips of the free veins. Indusium membranous, single, formed from 
the reflexed margin of the leaf-blade. Veins free. 



Lower divisions of the leaf-blades undivided. 1. P. lonrpfolia. 
Lower divisions of the leaf-blades forked or pinnate. 

Leaflets 7-10 mm. wide, the upper scarcely decurrent. 2. P. Cretica. 

Leaflets 5 mm. wide or less, the upper strongly decurrent, 3. P. serrulata, 

1. Pteris longifolia L. Leaves somewhat spreading ; petioles 15-30 cm. long, clothed 
below with pale brown scales ; blades oblong-lanceolate, 3-6 dm. long ; leaflets linear, 4-10 
mm. wide, entire, sessile : veins close, usually once branched : indusium yellowish brown. 

Peninsular Florida and the Keys, and Louisiana. Also widely distributed in the tropics, 

2. Pteris Crfetica L, Leaves several ; petioles 15-30 cm. tall, straw-colored or pale 
brown ; blades 15-30 cm. long ; leaflets usually 2-6 opposite pairs, sessile, the sterile con- 
siderably broader and spinulose-serrulate, the lower pairs often parted nearly to the base 
into 2 or 3 linear segments : indusium pale : veins free, parallel, simple or once forked. 

Peninsular Florida and the Keys. Also in tropical regions generally. 

3. Pteila senulkta L. f. Leaves several ; petioles 15-22 cm. long, naked, pale or 
brownish ; blades ovate, 20-45 cm. long, 2-pinnatifid, the rachis with a wing 2-4 mm. wide 
at the top, thence narrowed downward ; leaflets in 6 or more distinct opposite pairs, the 
upper simple, the lower with several elongated linear segments on each side ; tne sterile 
portions spinulose-serrate. 

On old walls, South Carolina to Louisiana, doubtless escaped from cultivation. A native of China. 

9. PTERIDIUM Scop. 

Coarse plants growing in open sunny places, with ternately compound leaf -blades. Sori 
marginal, linear, continuous, rising from a vein-like receptacle connecting the ends of free 
veins, Indusium double, an outer formed by the reflexed margin of the leaf-blade and a 
second, more delicate with the vein-like receptacle. 

Ultimate segments of the leaf-blades approximate at the base. 1. P. aquilinnm. 

Ultimate segments of the leaf-blades, 4-6 mm. apart at the base. 2. P. caudatum. 

1. Pteridium aquilinum (L.) Kuhn. Rootstock stout, woody, horizontal. Leaves 
erect, sometimes 2 m. tall ; petioles straw-colored or brownish, 3-6 dm. long ; blades 6-12 
dm, long, usually glabrous, ternate, the three divisions each 2-pinnate, the lower leaflets 
more or less pinnatifid. \^Pte7is aquilina L.] 

In sunny places, throughout North America, Europe and Asia. Variable. Bracken. Brakk. 

2. Pteridium caudatum ( L. ) Maxon. Leaves erect, 1-4 m. tall, or sometimes taller ; 
blades 3-4-pinnate ; divisions pinnatifid, the ultimate segments narrow, with recurved mar- 
gins, remote from one another, scarcely decurrent on the rachis except near the apex, the 
larger with 1-12 similar but shorter segments. [Pteris aquilina var. caudata (L.) Hook.] 

In sandy soil, Florida and Texas. Also in the West Indies, 



10. ADLA.NTUM L. 

Graceful plants of rocky hillsides, woods and ravines, with much divided leaf-blades. 
Petioles and their divisions slender or filiform, polished and shining. Sori short, margi- 
nal, borne on the under side of the reflexed and altered portion of the leaflets, which serves 
as an indusium. Maidenhair Fern. 



POLYPODIACEAE 



9 



Leaf-blades ovate-lanceolate or deltoid in outline, pinnately compound. 

Leaf-blades 1-2-pinnate: leaflets persistent. 1. A. Cap ilhts- Veneris, 

Leaf-blades 3-4-pinnate : leaflets deciduous, 2. A. tenervm. 

Leaf-blades roundish or reniform, dichotomously forked, with pinnate branches. 3. A. pedatum. 

1. Adlantum Capillus-V6neris L. Rootstocks creeping, slender, chaffy with light 
brown scales. Leaves numerous ; petioles very slender, black or nearly so, shining, 7-22 
cm. long ; blades ovate-lanceolate in outline, 2-pinnate below, 1-pinnate above, mem- 
branous, commonly drooping, 1.5-5 dm. long, 1-3 dm. wide at the base ; leaflets cuneate- 
obovate or rhomboid, rather long-stalked, glabrous, the upper margin incised, crenate or 
dentate-serrate except where it forms the indusia. 

In ravines, preferring limestone, Virginia to Missouri, South Dakota and California, south to 
Florida and Louisiana. Rare or local. Also in warm-temperate regions generally. 

2. Adiantum t^nerum Sw. Leaves several ; petioles 3 dm. tall, glossy ; blades del- 
toid, 3-9 dm. long, 2-4 dm. wide, 3-4-pinnate ; leaflets articulated at the base, and falling 
away at maturity, cuneate, the upper edge sometimes angular, broadly and often deeply 
lobed : sori numerous, roundish or transversely oblong. 

In sink-holes in lime-rock, central peninsular Florida. Also in tropical America. 

3. Adiantum pedatum L, Rootstocks slender, chaffy. Leaves numerous ; petioles 
2-4.5 dm. long, dark chestnut-brown, polished and shining, dichotomously and pedately 
forked ; blades nearly orbicular or reniform in outline, 2-4.5 cm. broad, the larger divi- 
sions 1.5-2.5 dm. long: leaflets oblong, triangular-oblong or the terminal one fan-shaped, 
all short-stalked, the upper margin toothed, cleft or lobed, bearing the linear-oblong sori. 

In woods* Nova Scotia to British Columbia and Alaska, south to Georgia, Mississippi and Califor- 
nia. Also said to occur in western Asia. Maidenhair Fern. 



11, PELLAEA Link. 

Rock-inhabiting plants, relatively small in size, with pinnate or pinnatifid leaf-blades. 
Sterile and fertile leaves similar : petioles usually dark colored. Sori intramarginal, borne 
on the ends of unconnected veins, at length confluent and forming marginal lines. In- 
dusium commonly broad, membranous, formed of the reflexed margins of fertile leaflets 
more or less modified, and membranous. Cuff-brake. 

Indusium broad : leaflets often narrow. 
Leaf-blades 1-2-pinnate. 

Leaflets obtuse or barely acute. 

Petioles and leaflets smoo:^h. 1. P. atropurpurea* 

Petioles and leaflets scurfy-pubescent. 2. P. aspera. 

Leaflets mucronate or decidedly acute. 3. P. Wrightiana, 

Leaf-blades 3-1-pinnate ; leaflets numerous. 4. P, puklieUa, 

Indusium very narrow : leaflets broad : rachis zigzag. 6. P. flexuoscu 

1. Pellaea atropurpurea (L, ) Link, Rootstocks short, densely clothed with rusty 
hair-like scales. Lea\'es tufted ; petioles 5-15 cm. long, dark purple or nearly black ; 
blades leathery, lanceolate or ovate-lanceolate in outline, 1-3 dm. long, simply pinnate or 
2-pinnate below; rachis dark-brown or purple; leaflets 2.5-5 cm. long, glabrous, some- 
times sessile : veins obscure, commonly twice forked. 

On rocks, preferring limestone, Ontario to British Columbia, Massachusetts, New Jersjey, Georgia 
and Arizona. 

2. Pellaea dspera (Hook.) Baker. Leaves several ; petioles slender, 5-8 cm. long, 
with scurfy pubescence ; blades oblong-lanceolate, 10-15 cm. lone, 2-pinnate ; leaflets del- 
toid-lanceolate or oblong, those next to the main rachis often lobed, all scabrous on both 
surfaces. 

On dry rocks, Texas and New Mexico. 

3. Pellaea 'Wrighti^na Hook. Rootstocks stout, densely chafTy. Petioles crowded, 
purplish brown, 10-15 cm. long ; leaf-blades lanceolate to deltoid, 10-25 cm. long, 2-pinnate, 
or 3-foliolate at the apex ; leaflets mucronulate, the ultimate ones often long and narrow ; 
spore-bearing ones with margins inflexed to the midrib. 

On rocks, Colorado to Texas and California. Also in Mexico. 

4. Pellaea puIch^Ua ( Mart. & Gal. ) F^e. Leaves clustered ; petioles 7-15 cm. long, 
chaffy at the base, nearly black ; blades 7-18 cm. long, triangular ovate, 4-pinnate below, 
l^radually simpler above ; leaflets numerous, oval or cordate-ovate, 2-6 mm. long, stalked, 
ieathery, smooth. 

In dry places, western Texas and New Mexico. Also from Mexico to Chile. 

5. Pellaea flexu&sa (Kaulf. ) Link. Kootstocks slender. Leaves several ; petioles 
reddish, passing into the zigzag rachis, with deflected and zigzag nearly smooth secondary 



10 



POLYPODIACEAE 



and tertiary divisions ; blades ovate-oblong, 15-75 cm. long, 2-pinnate, primary divisions 
mostly alternate : leaflets roundish ovate or nearly cordate-ovate, 10-20 mm. long, smooth. 



On ciry rocks, Texas to California. Also in Mexico. 

12. CHEILANTHES Sw. * 

Rock-inhabiting ferns, often small, usually with pubescent foliage. Leaves various : 
blades much divided. Sori terminal on the veins, ultimately more or less confluent. In- 
dusium formed of the reflexed margins of the leaflets, roundish, sometimes more or less 
confluent. Sporanges often much concealed in the scales of tomentum. Lip-Ferx. 

Indusium not continuous around the leaf-segments. 

Leaf-segments glabrous. -, ri a? t. 

Leaf-blades 2-pinnate ; lower leaflets not enlarged. L 6. Alnbamei^fns, 

Leaf-blades nearly or quite 3-pinnate ; lower leaflets enlarged. 2. a micropnyua. 

Leaf-segments pubescent and glandular, not tomentose. 0^7 

Leaf-blades deltoid-ovate ; petioles straw-colored. 3. C. (eticopoaa. 

Leaf-blades ovate-lanceolate ; petioles brownish. 4. C. lanosa. 
Indusiura continuous around the margins of the leaf-segments. 

Leaf-blades tomentose below, hairy above. = ^ t- • 

Leaf-blades 5-10 cm. long ; petioles slender, becoming nearly glabrous. 5. C. I'eei. 

Leaf-blades 1^-45 cm. long; petioles stout, densely brown-tomentose. 6. C. to^naitosa. ^ 

Leaf-blades scaly and tomentose beneath, white-tomentose above. /. C. Lindheimen. 

1. Cheilanthes Alabam^nsis (Buckl.) Kunze. Eootstocks horizontal, stout, with 
brown scales. Petioles black, 7-18 cm. long, wiry, rusty-villous at least below; leaf-blades 
lanceolate, glabrous, 5-25 cm. long, 2-pinnate ; leaflets numerous, ovate-lanceolate, acu- 
minate, the lower usually smaller than those above, pinnatifid ; segments mostly acute, often 
auriculate on the upper side at the base: indusia pale, membranous, interrupted by the in- 
cising of the segments. 

On rocks, Virginia to Alabama, Arkansas and Arizona. Also in Mexico. 

2. Cheilanthes microphylla Sw. Eootstocks with slender brown scales. Petioles 
dark brown, glossy, rusty-pubescent on the upper side, 10-15 cm. long ; leaf-blades ovate- 
lanceolate, 10-25 cm. long, 2-pinnate ; lower divisions larger and more deltoid than the 
upper; leaflets deeply incised or pinnatifid : indusium similar to the leaf-blade in texture, 
interrupted or nearly continuous. 

On shell heaps, Florida. Also in New Mexico and tropical America. 

3. Cheilanthes leucdpoda Link. Eootstocks stout. Petioles 8-25 cm. long, chaffy 
at the base ; leaf-blades broadly deltoid-ovate, 5-8 cm. long, 4-pinnate at the base, gradu- 
ally simpler above, everywhere glandular-puberulent, lowest pair of pinnae inequilaterally 
deltoid, upper oblong ; leaflets short-stalked, the lobules strongly revolute when fertile. 

On rocks, Uvalde Caiion, Texas. Also in Mexico. 

4. Cheilanthes lanosa (Michx.) Watt. Eootstocks with pale rusty-brown seal 
Petioles tufted, wiry, chestnut-brown, 5-10 cm. long, hirsute; leaf-blades evergreen, her- 
baceous, oblong-lanceolate, 10-22 cm. long, gradually attenuate to the apex, 2-pinnate; 
leaflets somewhat distant, lanceolate-deltoid, acute, deeply pinnatifid or incised, more or 
less covered with almost bristly hairs and usually somewhat glandular : sori numerous, 
covered by the infolded ends of the rounded or oblong lobes. [C. vestita Sw.] 

On rocks. Connecticut to Missouri, middle Georgia and Texas. 

^ 5. Cheilanthes Fe%i Moore. Eootstocks with narrow brown scales lined with black. 
Petioles densely tufted, slender, at first covered with woolly hairs, at length nearly glabrous ; 
leaf-blades about as long as the petioles, ovate-lanceolate, 5-10 cm. long, 3-pinnate or 2- 
pinnate with the leaflets pinnatifid, the upper surface slightly tomentose, the lower densely 
matted with whitish brown woolly hairs ; upper pinnae oblong-ovate, the lower deltoid, the 
lowest distant ; leaflets or their lobes minute, the terminal ones slightly larger than the 
others, all roundish or obovate and much crowded : indusium narrow. 

On rocks, Minnesota to British Columbia, Illinois, Texas and Arizona. 



^ 6. Cheilanthes tomentosa Link. Eootstocks densely chaffy with light brown scales. 
Petioles tufted, 1-2 dm. long, rather stout, densely brown-tomentose ; leaf-blades oblong- 
lanceolate, 3-pinnate, 1.5-4.5 dm. long, densely tomentose, especially beneath, with slender 
brownish white obscurely articulated hairs ; leaflets ovate-oblong or oblong-lanceolate, the 
ultimate division about 1 ram, long, the terminal ones sometimes twice as large as the 
others : indusium pale, membranous, continuous. 

On rocks, Virginia to Missouri, Georgia, Texas, Arizona and Mexico. 

7. Cheilanthes Llndheimeri Hook. Eootstocks slender, chaffy. Petioles scattered, 
10-18 cm. long, black-brown, covered with scales and wool when young ; leaf-blades ovate- 



POLYPODIACEAE 



11 



lanceolate, 8-20 cm. long, 3-4-pinnate ; leaflets crowded, 0.5 mm. long, white-tomentose 
above, very chaffy beneath. 

On rocks, Llano County, Texas to Arizona and northern Mexico. 



13. NOTHOLAENA E. Br. 



/ 



Eelatively small rock-inhabiting plants with tomentose scaly or powdery foliage. 
Leaves various : blades 1-4-pinnate or pinnatifid, Sori roundish or oblong, soon con- 
fluent into a narrow band. Indusium wanting : sporanges sometimes at first covered by 
the inflexed leaf-margins. Veins free. 

Leaf-blades covered with white or yellow powder beneath. 

Leaf-blades 3-1-pinnate at tlie base. 1. N. dealbata. 

Leaf-blades barely 2-pinnate. 

Leaf-blades deltoid-ovate, white-powdery beneath. 2. N. Candida, 

Leaf-blades pentagonal* yellow-powdery beneath. 3. N. Hookeri. 

Leaf-blades scaly or tomentose beneath. 

Leaf-blades 1-pinnate. narrow, elongated. 4. N, sinuata. 

Leaf-blades 3-pinnatifid, oblong-lanceolate. 5. N. Ascheiiboniiana . 

1. Notholaena dealbata (Pursh) Kunze. Rootstock chafTy with narrow brown 
scales. Petioles tufted, wiiy, shining, dark brown, 2.5-4.5 cm. long; leaf-blades triangu- 
lar-ovate, acute, broadest at the base, 2.5-10 cm. long, 3-pinnate, the rachis black and 
shining; leaflets ovate or obovate, obtuse, lobed, crenate or entire, small, scarcely 2 mm. 
long, white and powdery on the lower surface. 

On calcareous rocks, Missouri and Kansas to Texas and Arizona. 

2. Notholaena Candida (Mart. & Gal.) Hook. Eootstocks with rigid nearly black 
scales. Petioles tufted, 7-15 cm. long, wiry, black and shining; leaf-blades deltoid, pin- 
nate, rather shorter than the petioles ; leaflets various, the lower with the lowest inferior 
segments elongated and again pinnatifid, the 3 or 4 successive pairs lanceolate, upper leaflets 
resembling the segments of the lower, white-powdery beneath, slightly revolute. 

On rocks, Texas and New Mexico. Also in Mexico. 

3. Notholaena Hookeri D. C. Eaton. Rootstocks densely covered with rigid dark- 
Thrown scales. Petioles tufted, 10-20 cm. long, reddish brown, wiry, shining; leaf-blades 
nearly pentagonal, 5-8 cm. in diameter, of 1 terminal and 2 lateral divisions ; terminal 
division pinnatifid into a few toothed segments, the second pair larger than the first ; 
lateral divisions bearing a single large pinnatifid basal segment on the lower side and above 
it pairs of smaller ones, covered beneath with pale yellow powder. 

On rocks, Uvalde Caiion, Texas, west to Arizona. 

4. Notholaena sinukta (Sw.) Kaulf. Eootstocks very chaffy. Petioles erect, 
5-10 cm. long ; leaf-blades simply pinnate, 15-60 cm. long ; leaflets numerous, short- 
stalked, roundish or ovate, entire or pinnately lobed, densely scaly beneath, with merely 
scattered hairs above. 

On rocks, San Saba Texas, to Arizona and Mexico. Also In tropical America. 

. 5. Notholaena Aschenbornikna Kl. Kootstocks short. Petioles tufted, 5-8 cm. 
long, wiry, blackish, densely scaly ; leaf -blades oblong-lanceolate, 10-25 cm. long, 3-pin- 
natifid ; segments lanceolate, cut into linear-oblong, crenate or pinnatifid ultimate seg- 
ments, pale green above, densely mottled beneath with linear ciliate ferruginous scales 
and also somewhat mealy ; sori black. 

On rocks, Texas to southern Arizona and Mexico. 

4 

14. BLECHNUM L. 

Coarse swamp plants, with stout rootstocks. Leaves clustered : blades thickish. Sori 
linear, contiguous or nearly so, parallel to the midrib and usually contiguous to it. In- 
dusium membranous, distinct from the edge of the leaf-blade. Veins free. 

1. Blecbnum aerrul^tum L. C. Rich. Petioles erect, nearly naked, 15-30 cm. long, 
stout ; leaf-blades oblong-lanceolate, 30-60 cm. long, leathery, with 12-24 pairs of linear- 
oblong leaflets ; margins very finely incised : veins very fine and close : fertile leaves with 
much narrower blades than those of the sterile. 

In swamps, Florida, Also in tropical America, 

15. ANCHISTBA Presl. 
Large and rather coarse swamp ferns, with short oblong sori sunk in cavities in the leaf 



iged 



Leaves uniform. Indusia fixed by 



12 POLYPODIACEAE 



8., j4. angustifolium. 
9." A.flrmum, 



their outer margins. Veins forming a single line of areolae next the midrib, then free to 
the margin. 

1. Anchistea Virginica (L.) Presl. Kootstock stout, chaffy. Petioles stout, 3-4.5 
dm. long, nearly or quite naked, dark-colored below ; leaf-blades oblong-lanceolate, acute, 
narrowed at the base, 3-6 dm. long, 15-22 cm. wide, pinnate ; leaflets linear-lanceolate^ 
usually alternate, or some of them opposite, leathery, glabrous, acuminate, sessile, 7-15 
cm. long, deeply pinnatifid into ovate or oblong obtuse segments, their margins minutely 
serrulate. [Woodward ia Virginica (L. ) J. E. Smith.] 

In swamps and meadows, Nova Scotia to Ontario, Michigan, Florida, Louisiana and Arkansas. 

16. ASPLENIUM L. 

Plants various in habit and habitat. Leaves tufted : blades entire, lobed, pinnatifid 
or 1-3-pinnate, mostly uniform. Sori linear or oblong, oblique to the midrib or rachis. 
Veins free. Indusia straight or curved, opening towards the midrib when single. Spxkex- 

WORT. 

Sori straight or rarely slightlv curved, attached to the upper side of a vein. 

Leaves with simple crenulate or serrulate blades : plants 4-7 dm. tall. 1. A. serratum. 

Leaves with pinnatifid or pinnate blades. 
Leaf-blades pinnatifid or pinnate. 

Leaf-blades pinnatifid, or pinnate merely below. 

Petioles green above, blackish below ; leaf-lobes normally rounded. 2. A. pinnatUidxim, 
Petioles black throughout: leaf-lobes normally acuminate. 3. A. ebenoiaes. 

Leaf-blades pinnate. 

Leaflets 0.7-3 cm. long, mostly blunt. 
Rachis chestnut-brown or blackish. 

Leaflets auricled at the upper side of the base. 

Leaflets opposite, oblong : rachis dark brown or black. 4. A. resilicfis. 

Leaflets partly alternate, lanceolate: rachis chestnut-brown. 5. A^ plafyneiiron. 
Leaflets not auricled. . 6. A. Trichomanes. 

Rachis green : leaflets not auricled, crenate. 7, A, daitatum. 

Leaflets 4-12 cm. long : acute or acuminate. 
Leaf-blades 7-9 dm. long. 
Leaf-blades 2.5-5 dm. long. 
Leaf-blades 2-3-pinnatifid : 
Texture leathery. 

Petioles green : leaf-blades rhombic or obovate, the veins flabellate, 10. A, Rata-mararia. 
Petioles dark below : leaf-blades ovate-lanceolate. 11. A, montanum. 

Texture herbaceous or membranous. 

Petioles and the lower part of the rachis chestnut-brown. 12. A, BradJeyi, 

Petioles green or greenish. 

Leaf-segments linear or oblong, narrow. 13. A, cicutarium. 

Leaf-segments rounded, entire or 2-3-lobed. 14, A. myriophyllum, 

Sori more or less curved, sometimes horseshoe-shaped, often crossing to the outer 
or lower side of the veinlet : large plants. 
Leaf-blades 2-pinnatifid ; segments blunt, scarcely crenate. 15. A, acrostichoides. 

Leaf-blades 2-pinnate ; leaflets acute, toothed or pinnatifid. 16. A, Filix-foeinina. 

1. Asplenitim serratum L, Leaves in a crown from a stout erect rootstock ; blades 
spatulate or linear-oblanceolate, 4-7 dm. long, crenulate or irregularly serrulate, somewhat 
leathery ; midrib keeled and often blackish purple beneath ; veins free, approximate, once- 
forked : sori elongated, following the veins of the upper half of the blade from near the 
midrib half way to the margins : indusia single, the free edge entire. 

In swamps, peninsular Florida. Also in tropical America. 

2. Asplenium pinnatifidum Nutt. Rootstock short, chaffy. Leaves tufted ; petioles 
polished, blackish below, green above, 5-12 cm. long, somewhat chaffy below, at least when 
young ; blades broadly lanceolate in outline, 7-25 cm. long, firm, tapering upward to a long 
narrow tip, pinnatifid or the lower parts pinnate ; lowest segments, or occasionally several 
pairs, sometimes tapering to a point like that of the apex of the leaf. 

On rocks, New Jersey to Illinois and Arkansas, and in the mountains to Georgia. 

3. Asplenium ebenoidea E. R. Scott. Rootstock short, chaflTy. Leaves tufted ; 
petioles blackish, 4-10 cm. long ; blades lanceolate, variable, 8-25 cm. long, firm, tapering 
to a very long narrow acuminate apex, pinnatifid, or commonly pinnate below, the seg- 
ments lanceolate from a broad base, acute or acuminate, irregular, the lower sometimes 
shorter than those just above : sori several on each segment, straight or slightly curved. 

On limestone, Connecticut to Indiana and Alabama. Rare, except at a single locality in Alabama. 

4. Asplenium resiliens Kunze. Kootstock short, with black stiff scales. Leaves 
tufted ; petioles blackish and shining, 2.5-5 cm. long ; blades rather firm, linear-oblong or 
linear-oblanceolate, 7-25 cm. long, 1-pinnate ; leaflets 4-12 mm. long, mostly opposite, 
oblong, obtuse, entire or crenulate, auricled on the upper side and nearly sessile, the middle 
ones the longest, the lower gradually shorter and reflexed : rachis dark brown or black : 



■,\^ -m i.^ J-n^ ^C_ ... J — ^ ~ ri—.--. 



POLYPODIACEAE 



13 



sori oblong, borne about midway between the midrib and the margin of the blade, nearly 
or quite straight. [A, parvulum Mart. & Gal., not Hook.] 

Often on limestone, Virginia to Missouri, Florida, Texas, New Mexico and Mexico. 

5. Asplenium platyneuron (L.) Oakes. Eootstock short. Leaves evergreen, tufted ; 
petioles purplish brown and shining, 2.5-10 cm. long ; blades linear, 2-4 cm. long, firm, 
pinnate, the rachis chestnut-brown ; leaflets 20-40 pairs, lanceolate, subfalcate, alternate 
or partly so, sessile, crenate, serrate or incised, auricled on the upper side at the base and 
occasionally also on the lower ; lower leaflets gradually smaller and oblong, or triangular : 
sori 8-12 on each side of the midrib, crowded at maturity. lA. ebeneum Ait.] 

On rocks and shaded slopes, Maine and Ontario to Colorado, south to Florida and Texas. 

6. Asplenium Trichdmaiies L. Rootstock short, nearly erect, with blackish scales. 
Leaves densely tufted, numerous; petioles 2.5-12 cm. long, purplish brown and shining ; 
blades linear in outline, 7-20 cm. long, rather rigid, pinnate, evergreen ; leaflets oval or 
roundish oblong, inequilateral, cuneate at the base, their margins slightly crenate ; sori 
3-6 on each side of the forking and evanescent midrib, short, narrowed at both ends. 

On rocks, preferring limestone, nearly throughout North America. Also in Europe and Asia. 

7. Asplenium dentdtum L. Petioles tufted, 5-15 cm. long, naked, l)lack]sh below. 
Fertile leaf-blades 5-7.5 cm. long, with 6-8 pairs of stalked oblong or rhombic leaflets, the 
lower side truncate with a curve, the outer edge irregularly crenate ; sterile leaves similar 
but wdth shorter petioles : rachis naked : sori copious, in parallel rows. 

In sandy soil, South Carolina to Florida. Also in the West Indies. 

8. Asplenium anguatlfollum Michx. Rootstock stout. Fertile leaves usually taller 
than the sterile. Petioles in a crown, chaffless, or merely scaly at the base, 2-3 dm. long, 
brownish or greenish above ; leaf-blades lanceolate, 3-8 dm. long, pinnate ; leaflets linear- 
lanceolate or those of sterile leaves lanceolate, in 20-30 pairs, acuminate, entire or crenulate, 
obtuse or truncate at the base : sori 20-30 on each side of the midrib, linear, crowded. 

In moist or rich woods, Quebec to Wisconsin, Virginia. Georgia and Alabama. 

9. Asplenium ffrtnum Kunze. Petioles 10-20 cm. tall, naked, grayish. Leaf-blades 
15-30 cm. long; leaflets oblong-lanceolate, 12-20 pairs, blunt-pointed, minutely crenulate, 
the upper margin abruptly narrowed at the base, the lower obliquely truncate : sori short, 
not reaching either margin or midrib. 

In caverns, peninsular Florida. Also in the West Indies. 

10. Asplenium Ruta-mur^ria L. Eootstock ascending. Leaves tufted ; petioles 
naked, green, 5-7 cm. long; blades ovate or deltoid-ovate, 5-12 cm. long, glabrous, ever- 
green, 2-3-pinnate, or pinnatifid above ; leaflets stalked, rhombic orobovate, mostly obtuse, 
dentate or incised, cuneate at the base ; veins flabellate : sori few, linear-oblong, confluent 
when mature and nearly covering the leaflet: indusia membranous and delicate. 

On limestone, Vermont to Michigan and Missouri, south to Connecticut, Alabama and Arkansas. 
Also in Europe, Asia and northern Africa. 

11. Asplenium mont^num Willd. Eootstock chaffy at the summit. Leaves tufted ; 

{)etioles naked, slender, blackish at the base, 5-7 cm. long; blades 5-20 cm. long^ ovate- 
anceolate in outline, acuminate, rather firm, 1-2-pinnate ; lower leaflets longest, pinnate or 
pinnatifid, the lobes or segments ovate or oblong ; upper less divided, merely toothed or in- 
cised ; veins obscure : sori linear-oblong, short, the lower ones sometimes double. 

On rocks, Connecticut to Ohio and Arkansas, and in the mountains to Georgia and Alabama. 

12- Asplenium Bradleyi D. C. Eaton. Rootstock chaffy with brown scales. Leaves 
tufted; petioles slender, 5-7 cm. long, chestnut-brown ; blades oblong-lanceolate or oblong, 
acuminate, not narrowed at the base, with 8-12 pairs of f^hort-stulked or sessile oblong- 
ovate leaflets ; the lower again pinnatifid or pinnate, >vith oblong obtuse lobes or pinnules, 
which are toothed at the apex, the upper pinnatifid with dentate or nearly entire lobes : 
rachis brown : sori near the midrib, covered with the narrow indusia until mature. 

On rocks, often preferring limestone, New York to Illinois and Missouri, south to middle Georgia, 
Alabama and Arkansas. 

13. Asplenium cicutArium Sw. Petioles greenish, tufted, 10-20 cm. long, naked. 
Leaf-blades 15-38 cm. long, with 10-15 pairs of horizontal leaflets, the lower ones 5-7.5 
cm. long, palled into linear or oblong segments which are once or twice cleft at the apex : 
rachis compressed and often winged : son mainly in 2 rows. 

In swamps, Sumter County, Florida. Also in tropical America. 

14. Asplenium myriophyllum Mett. Petioles tufted, 5-15 cm. long. Leaf-blades 
lanceolate, 8-30 cm. long, 2-3-pinnatifid ; segments entire, or 2-3-lobedj each bearing a 
single vein and a sorus. 

On rocks in sink-holes, peninsular Florida. Also in tropical America.— A form with narrowly 
linear leaf-blades 1.8-2.5 cm. wide, and 7-8-lobed widely ascending leaflets, is known as A, myriophyllum 
BUcaynednum D. C. Eaton. 



14 



rOLYPODIACEAE 



Also 



15. Asplenlum acrostichoides Sw. Rootstock sinuous. Tetioles 2-3 dm. long, 
straw-colored, somewhat chafFy below at least when young; leaf-blades lanceolate in out- 
line, 3-0 dm. long, acute or acuminate at the apex, narrowed to the base, pinnate-pinnatilid ; 
leaflets linear-lanceolate, sessile, acuminate, deeply pinnatitid into numerou>i^ oblong obtuse 
or subacute, slightly crenate segments : sori crowded, slightly curved, or straight, the lower 
ones often double : indusium light-colored and somewhat shining when young. 

In rich moist woods, Nova Scotia to Minnesota, south to CTCorgia and Louisiana. Also in Asia. 

16. Asplenium Filix-fofemlna (L. ) Bernh. Rootstock rather slender for the size of 
the plant. Petioles tufted, 0.5-2.5 dm. long, straw-colored, brownish or reddish; leaf- 
blades broadly oblong-ovate or oblong-lanceolate, acuminate at the apex, 3-9 dm. long, 2- 
pinnate ; leaflets lanceolate, acuminate, short^stalked or the upper ones sessile, 1-2 dm. 
long, the ultimate divisions oblong-lanceolate, incised or serrate, their lobes or teeth often 
again toothed, those toward the ends of the leaflets confluent by a very narrow margin to 
the secondary rachis : sorl short, the indusia straight or variously curved, sometimes horse- 
shoe-shaped. 

In wet woods and thickets, Nova Scotia to Alaska, south to Florida, Louisiana and Arizona, 
in Europe and Asia. Very variable. 

17. PHYLLITIS Ludwig. 

Large ferns with oblong or strap-shaped mostly entire leaf-blades. Sori linear, elon- 
gated, almost at right angles to the midrib and contiguous in pairs, one on the upper side 
of a veinlet, the other on the lower side of the next contiguous veinlet, thus appearing to 
have a double indusium opening longitudinally along its middle. \_Scolopendriuni Adans. ] 

1. Phyllitls Scolop^ndrium (L. ) Newman. Rootstocks short, chaffy Avith light 
brown scales. Petioles 5-15 cm. long, fibril) ose-chaflTy below or sometimes up to the top ; 
leaf-blades entire, bright green, firm, 2-4.5 dm. long, cordate at the base, pairs of sori dis- 
tinct, 4-15 mm. long, conspicuous : veins free, usually once forked near the midrib. 
\^Scolopendrium vulgare J, E. vSmith.] 

On shaded limestone cliffs, New Brunswick to Ontario and New York, south to Tennessee. Also 
in Europe, Asia and Africa. Hart's Tongue. 

18. CAMPTOSORUS Link. 
Slender plants, with tapering simple entire or undulate leaf-blades. Sori linear or ob- 
long, several times longer than broad, irregularly scattered on either side of the reticulate 
veins or sometimes crossing them, partly parallel to the midrib and partly oblique to it, the 
outer ones more or less approximate in pairs. Indusium membranous. 

1. Camptosonis rhizophyllus (L.) Link. Rootstock short, chaffy. Petioles light 
green, 2.5-15 cm. long, tufted, spreading ; leaf-blades rather thin, lanceolate, simple, long- 
acuminate at the apex, cordate, hastate or rarely narrowed at the base, 10-25 cm. long, 
sometimes with a more or less elongated pair of basal auricles ; tip of the leaf and sometimes 
the tip of one or both of the basal auricles rooting and forming a new plant by the ultimate 
withering away of its tissue : sori usually numemus, irregularly scattered. 

On rocks, preferring limestone, Quebec to Ontario and Minnesota, south to Georgia and Kansas. 
M ALKiNG Leaf. Walking Fern. 

19. LORINSERIA Presl. 

Rather coarse ferns of swamps, with dimorphous leaves and rather large linear sori 
sunk in cavities in the leaf and arranged in chain-like rows. Indusia rather leathery, fixed 
by their outer margins and covering the cavity like a lid. Veins forming copious areolae. 

1, Lorinseria areolkta (L. ) Presl. Rootstock slender, chaffy. Leaves of two kinds, 
the fertile taller than the sterile and their blades borne on longer petioles, 3-6 dm. high, 
their segments much contracted, narrowly linear, 7-12.5 cm. long, 4-6 mm. wide, distant, 
their bases connected by a very narrow wing along the rachis or quite distinct ; sterile leaf- 
blades deltoid-ovate, membranous, broadest at the base, or sometimes with one or two small 
segments below, acuminate, the segments lanceolate or oblong-lanceolate, minutely serru- 
late, sometimes undulate, their bases connected by a rather broad rachis-wing. [ Wood- 
uurdia angustifolia J. E. Smith.] 



Arkansas 



20. ONOCLEA L. 



Ferns with elongated horizontal rootstocks. Leaves growing separately. Fertile leaf- 
blades closely rolled up into berry-like segments, and entirely unlike the broad pinnatifid 



POLYPODIACEAE 



15 



sterile leaf-blades. Sori ronnd, borne on the back of the veins. Indusium verv thin and 
membranous, hemispheric or hood-shaped, fixed at the inferior side of the sorus. Sporo- 
phylls unrolling at maturity, allowing the spores to escape, and remaining long after the 



sterile leaves have been killed by frost. Veins forming small areolae. 

1. Onoclea sensibilis L. Leaves 3-13 dm. high ; blades triangular, deeply pinnati- 
fid ; segments lanceolate-oblong, entire, undulate, or the lower pairs sinuate-pinnatifid : 
sporophylls 3-7 dm. high, persistent over winter, much contracted and with short pin- 
nules rolled up into berry-like closed involucres forming a narrow panicle. 

In moist soil, Newfoundland to Ontario and Minnesota, south to the Gulf of Mexico.— Various 
forms intermediate between sporophylls and foliage leaves occur. Summer and fall. SiiTNSiTivE Fern. 

21. TECTARIA Cav. 

Plants Avith horizontal rootstocks. Sori round, borne on the back of the leaflets or 
leaf-segments. Indusium peltate, opening all around the margin. Veins everywhere 
anastomosing, forming copious areolae, with free included veinlets. 

1. Tectaria trifoli^ta (L. ) Cav. Leaves tufted, 6-7.5 dm. tall; petioles brownish, 
scaly at the base ; leaf-blades 3-4.5 dm. long, each with a large ovate-acuminate terminal 
leaflet narrowed or forked at the base, and 1 or 2 lateral leaflets, the lowest mostly forked : 
primary veins distinct to the margin : areolae fine : sori in 2 rows near the main veins : 
indusia orbicular, peltate. \_Aspidium trifoliatum (L. ) Sw. ] 

In sandy soil, peninsular Florida and Texas. Also in tropical America. 

22. POLYSTICHUM Roth. 

Coarse plants, often with chaffy foliage. Leaves tufted : petioles not jointed to the 
rootstock ; blades 1-2-pinnate, the sterile and fertile similar. Sori usually borne on the 
backs of the veins. Indusium superior, centrally peltate, orbicular. Veins free. 

1. Polystichum acrostichoides (Michx.) Schott. Rootstocks stout. Leaves ever- 
green, 2.5-8 dm. tall ; petioles densely chaffy ; blades lanceolate, those of the fertile ones 
contracted near the top, 1.5-6 dm. long, 1-pinnate ; leaflets somewhat leathery, linear- 
lanceolate, 2.5-7 cm. long, falcate, half-hastate at the base, with appressed bristly teeth, 
bearing the large contiguous sori, which soon cover the whole lower surface near the mid- 
dle. [Aspidimn acrostichoides (Michx.) Sw.] 

. In woods and on rocky banks, Xova Scotia to Wisconsin, south to Forida and Mississippi. Christ- 
mas Fern. 

23. DRYOPTERIS Adans, 

Terrestial plants with erect or horizontal rootstocks. Leaves tufted, the sterile and 
fertile similar : blades 2-3-pinnate or -pinnatifid : petioles not jointed to the rootstocks. 
Indusium flattish, cordate-reniform, superior, fixed by the sinus. Veins free or basal 
veinlets united. Often known as Shield-ferns. 

Leaf-blades thin-membranous : veins simple or l-forked. 
Lower leaf-segments reduced to mere lobes. 

Rootstock stout, erect, forming a short caudex. 1. D. contermina, 

Rootstock slender, horizontal. . 2. D. Noveboracensis, 

Lower leaf-segments little smaller than the central. 

Veins forked : leaf-blades dark green, relatively firm. 3. D. ThclypterU, 

Veins simple : leaf-blades pale green, thin-flaccid. 4. Z>. patens. 

Leaf-blades firm or leathery : veins freely forking. 
Leaf-blades 2-3-piunatifid : veins always free. 

Leaf-blades 2-pinnatifid or 2-pinnate : divisions not spinulose. 
Indusia large, thinnisn, flat : sori midway to the margins. 
Leaflets or segments broadest at the base. 

Fertile and sterile leaflets alike, deltoid or triangular. 5. D. cristata. 

Fertile leaflets narrowly lanceolate, unlike the sterile ones. 6. D, Florirfana, 

Leaflets or segments broadest at the middle. 7. D, Goldieana. 

Indusia convex, without marginal glands: sori near the margin. 8. Z>. marginalis. 

Leaf-blades 2-pinnate or 3-pinnatifld : divisions spinulose-tipped. 9. D, spivulosa. 

Leaf-blades pinnate : contiguous veinlets united. 10. B, unita. 

1. Dryopteris cont6rmIna (AVilld. ) Kuntze. Kootstocks erect, often 3 dm. above the 
surface of the ground. Leaves in a crown ; petioles narrowly wing-margined at the base ; 
blades 3-12 dm. long, lanceolate, cordate-acuminate at the apex, rather rigid, narrowed at 
the base ; leaflets sessile, narrowly lanceolate from a broader base, acuminate, deeply pinnat- 
ifid ; segments obtuse, obliquely and slightly falcate, copiously resinous-dotted beneath : 
sori near the margins : indusia minute, reniform, glandular and pilose, evanescent. 

In swamps near Fort Meade, Florida.— The form within our range is known as D. contermina 
strlgdsa (Fee) Underw., to which the above description mainly applies. 



16 



POLYPODIACEAE 



blades 



2. Dryopteris Noveborac^nsis (L. ) A. Gray. Rootstocks slender, horizontal. Leaf- 
s lanceolate, tapering both ways from the middle, 3-6 dm. long, menabranous, long- 
acuminate, pinnate ; leaflets lanceolate, sessile, long-acuminate, deeply pinnatifid, ciliate 
and finely pubescent beneath, 3-7 cm. long, the two or more lower pairs gradually shorter 
and deflexed, commonly distant ; segments flat, oblong, obtuse, the basal ones often en- 
larged : veins simple, or those of the basal lobes forked ; sori not confluent, borne near 
the margin : indusia minute, reniform, delicate, glandular. 

In moist or swampy woods, Newfoundland to Ontario and Minnesota, south to Georgia, Alabama 
and Arkansas. 

3. Dryopteris Thelypteris (L. ) A. Gray. Rootstocks slender. Leaf -blades lanceo- 
late or oblong-lanceolate, scarcely narrower at the base than at the middle, 3-8 dm. long, 
short-acuminate, membranous, pinnate; leaflets linear-lanceolate, short-stalked or sessile, 
mostly horizontal, acuminate at the apex, nearly truncate at the base, 3-7 cm. long, slightly 
pubescent beneath, deeply pinnatifid ; segments oblong, obtuse, or appearing acute from 
the strongly revolute margins : veins regularly once or twice forked : sori crowded, 10-12 
to each segment : indusia reniform, slightly glandular, or glabrous. 

In marshes, New Brunswick to Manitoba, south to Florida and Texas. Also in Europe and Asia. 

4. Dryopteris patens (Sw. ) Kuntze. Rootstocks stout. Leaves several together; 
blades ovate-oblong, 4-12 dm. long, softly pubescent beneath ; leaflets approximate, linear, 
acuminate, the broadest pair somewhat reflexed, all cleft three-fourths the way to the mid- 
rib ; segments numerous, the basal ones longest : veinlets manifest, the lowest ones of 
adjacent segments often uniting : sori near the margins : indusia very pubescent. 



In sandy soil or on calcareous rocks, Georgia and Florida to California. 

5. Dryopteris cristkta (L. ) A. Gray. Rootstocks densely chaffy. Leaves ever- 
green ; petioles of the sterile leaves 5-12 cm. long, those of the fertile 1.5-2.5 dm. long ; 
blades linear-oblong or lanceolate, acuminate, gradually and slightly narrowed to the 
base, rather firm, 3-8 dm. long, pinnate ; leaflets lanceolate or triangular-ovate, acumi- 
nate, deeply pinnatifid or the lower pinnate, the segments 6-10 pairs, serrate or incised : 
sori about midway between the margin and midrib : indusia thin, glabrous. 

In wet woods and swamps, Xewfoundland to Manitoba, south to Kentucky and Arkansas. Also 
in Europe and Asia. 

6. Dryopteris Floridina (Hook.) Kuntze. Leaves clustered ; petioles 15-25 cm. 
long, with few ovate scales ; blades lanceolate, 45-50 cm. long ; leaflets various ; fertile 
confined to the upper half of the leaf-blade, narrowly lanceolate, cut nearly to the rachis 
into oblong segments ; sterile leaflets broader, shorter below, less deeply cut. 

In swamps, Georgia, Florida and Alabama. 

7. Dryopteris Goldie^na (Hook.) A. Gray. Kootstocks chaflTv. Petioles 2.5-4.5 
dm. long, chaffy at least below ; leaf -blades ovate, rather firm, 6-12 d*m. long, glabrous or 
nearly so, dark -green above, pinnate or nearly 2-pinnate ; lower leaflets broadly lanceolate, 
widest at about the middle, 1.5-2.5 dm. long, parted into about 20 pairs of oblong-linear 
subfalcate segments which are serrate with appressed teeth : sori very near the midrib, 
close together but distinct, large : indusia orbicular, glabrous, persistent. 

In rich woods. New Brunswick to Minnesota, south to North Carolina and the Indian Territory. 

8. Dryopteris marginMis (L.) A. Gray. Rootstocks ascending, with dark brown 
shining scales. Leaves evergreen ; petioles 7-20 cm. long, chaSy below ; blades ovate- 
oblong or ovate-lanceolate, rather leathery, 1.5-7.5 dm. long^ 1-2-pinnate, acuminate at 
the apex, slightly narrowed at the base ; leaflets numerous, lanceolate, nearly sessile, gla- 
brous, 5-12.5 cm. long, the lower broader and shorter than the middle ones, the upper 
pinnatifid, the lower pinnately parted into oblong obtuse entire dentate or pinnately lobed 
segments : sori distinct, close to the margin, covered by the glabrous indusia. 

In rocky woods, Prince Edward Island to Minnesota, south to Georgia, Alabama and Arkansas. 

9. Dryopteris spinulosa (Eetz) Kuntze. Leaves tufted, evergreen ; petioles bearing 
scales with dark centers ; blades ovate-lanceolate, usually not narrowed below, 2-pinnate ; 
leaflets narrowly triangular or the lower pairs broadly triangular, the ultimate segments 
oblique; connected by a very narrow^ wing, with spinulose-toothed lobes : indusia glabrous. 

In rich woods, Newfoundland to Alaska and Washington, south to Virginia and Michigan. Also 
m Europe aud Asia. Summer.— Two forms represent the species in our range : one. D. smniilosa intei^- 
media (Muhl.) Underw.. has oblong-ovate 2-3-pinnate leaf-blades and oblong-lanceolate spreading 
leaflets, the lowest unequally triangular-ovate : indusium beset with stalked glands. Its range extends 
southward to ^orth Carohna and Missouri. The other variety. D. spimdosa dilatdta (HoflFm.) Under w.. 
with broadly ovate or triangular-ovate commonly 3-pinnate blades, lanceolate-oblong ultimate (hvi- 

^^^r^^r'^V.^ lowest often much elongated, and glabrous indusia, ranges as far sonth as G^rgia. Tennessee 
ana Nebraska, . 

10. Dryopteris unita (L.) Kuntze. Leaves tufted ; petioles brownish, naked, about 
45 cm. long; blades 0.5-1 m. long, 12-20 cm. wide; leaflets narrow, the lower ones not 
reduced, cleft i to ^ the way to the midrib ; segments acute : veins pinnate in the broad 



rOLYPODIACEAE 



17 



segments, with 6-8 veinlets on eacli side of the lower ones of contiguous grouj)s : sori near 
the ends of the veins, mainly in the segments. 
In thickets, Florida. 

24. MATTEUCCIA Todaro. 
Stately ferns with large rootstocks. Leaves m crowns, tlie sterile and fertile different : 
blades pinnate or pinnatifid : sori round, borne on the veins of a contracted fertile leaf 
concealed by their revolute margins. Veins free. 

1 Matteuccia Stnithidpteris ( L. ) Todaro. Fertile leaves 3-5 dm. long; blades simply 
pinnate, with necklace-shaped leaflets formed of the strongly revolute margins ; sterile leaves 
6-18 dm. long; blades broadly lanceolate, 2-pinnatifid, the lowest leaflets gradually much 
shorter: veins pinnate: sori crowded, confluent. [Onoclea Strut hiopteris (L. ) Iloffm.] 

In moist thickets, especially on river banks, Nova Scotia to British ColumLia, south^td New Jei-sey 
and Arkansas. Ostrich Fern. 

25. PHEGOPTERIS Fee. 

+ 

Low rather tender ferns, with horizontal rootstalks. Leaves few, the fertile and sterile 
similar : petioles continuous with the rootstocks : blades ternate or 2-3-pinnatifid. Sori 
round, each on the back of a vein just below its tip or on the middle of the veinlets. In- 
dusium wanting or rudimentary. Veins free. Oak or Beech-ferx. 

1. Phegopteris hexagondptera (Michx. ) Fee. Rootstock chaffy, somewhat fleshy. 
Petioles 2-4.5 dm. long, straw-colored, naked; leaf-])lades triangular, as broad as long or 
broader, 2-3 dm. wide, slightly pubescent and often slightly glandular beneath, acuminate ; 
uppermost leaflets oblong, obtuse, dentate or entire, small, the middle ones lanceolate, 
acuminate, the very large lowest pair broadest near the middle, pinnately parted nearly to 
the midvein into linear-oblong obtuse segments : sori mostly near the margin. 

In dry woods, Quebec to Minnesota, south to Florida and Louisiana. 

26. GONIOPTERIS Presl. 

Eather large ferns of woods and rocky places, with horizontal rootstocks. Leaves pin- 
natifid or bipinnatifid. Sori on the back of the veins normally without an indusium. 
Veins connivent, the branches form contiguous groups uniting to form one or more arches. 

Sporiferous leaves of two sorts, one rigid, pinnatifid toward the apex, the other lax, pinnate through- 
out, and proliferous. 1. G, rrptana, 
:Sporiferous leaves of one sort, with large terminal leaflets. 2. G, tetragmia. 

1. Goniopteris r^ptans (Sw. ) Presl. Leaves spreading orprocumbent ; petioles 7-25 
cm, long, clustered, grayish straw-colored, slender, naked ; blades 10-30 cm. long, mem- 

l)ranous, softly pubescent with branched or stellate hairs, oblong-lanceolate, pinnate, with 
nearly or quite sessile crenately pinnatifid leaflets, the apex merely pinnatifid, often elon- 

;gated and rooting: veins pinnate, simple, the basal veinlets often anastomosing: sori on 
the middle of the veinlets, sometimes with a rudimentary indusium. 

w 

On calcareous rocks, middle and peninsular Florida. Also in the West Indies. 

2. Goniopteris tetrdgona (Sw. ) Presl. Leaves erect; petioles 15-45 cm. long, 
sometimes slightly villoys ; blades 3-6 dm. long, 15-30 cm. wide ; leaflets numerous, 
spreading, 7.5-15 cm. long, the lowest narrowed at the base and sometimes stalked, deeply 
pinnatifid, thin-herbaceous, the lower surface and the rachis finely pubescent : sori in rows 
near the midrib. 

In rocky woods, Marion County, Florida. Also in tropical America. 

F 

27. NEPHROLEPIS Schott. 

More or less epiphytic plants. Leaves spreading or pendent : blades elongated : leaf- 
lets numerous, approximate, jointed at the base, with whitish dots on the upper surface. 
^ori round, rising from the apex of the upper branch of a vein, usually near the margin. 
Veins free. 



7-15 cm, wide: indusia distinctly reniform 
20-30 cm, wide : indusia nearly orbicular. 



1. A', eraltata, 

2. N, biserrata 



1. Nephrolepis exaltAta (L. ) Schott. Petioles 10-15 cm. long; leaf-blades various, 
3-20 dm. long, 7-15 cm, wide ; leaflets lanceolate, sometimes crenulate, the upper side 
auricled at the base, the lower rounded ; the rachis nearly naked : sori almost marginal, 
covered with firm distinctly reniform indusia. 

On logs and stumps, peninsular Florida. Also in the tropics. Sword or Boston Fern. 

2. Nephrolepis bieerr^ta (Sw. ) Schott. Petioles 10-20 cm. long; leaf -blades 6-12, 
dm. long, 20-40 cm. wide ; leaflets 10-20 cm. long, acute, entire or crenulate, the upper 

2 



18 



POLYPODIACEAE 



side anricled, the lower rounded at the hase : rachis nearly naked : sori almost marginal, 
covered by nearly orbicular, rather peltate indusia. [N. acuta Presl.] 

On the south bank of the Miami River, Florida, Also in tropical regions. 

28. DENNSTAEDTIA Bernh. 

Rootstocks usually horizontal. Leaves tufted : blades 2-3-pinnatifid. Sori small, globu- 
lar marginal or nearly so. Sporanges borne in an elevated globular receptacle, enclosed in a 
membranous cup-shaped inferior indusium, -which is open at the top, and on the outer side 
adherent to a reflexed toothlet of the leaf. Veins always free. 

1. Dennstaedtia punctil6bula (Michx.) Moore. Rootstock not chaffy. Petiole* 
stout, chaffless, pale green and sweet-scented ; leaf-blades 3-10 dm. long, lanceolate, acute 



or acuminate, frequently long-attenuate, usually 3-pinnatifid, thin and delicate ; rachis and 

under surface minutely glandular and pubescent : sori minute, each on a recurved toothlet, 

usually one at the upper margin of each lobe : sporanges few : indusium cup-shaped with 

a delicate membranous irregular margin. \_Dicksonia pundilobula (Michx.) A, Gray.] 

On open hillsides, New Brunswick to Ontario and Minnesota, south to the mountains of Georgia- 
and Alabama. 

29. PILIX Adans. 

Delicate rock ferns. Leaves with slender petioles and 2-4-pinnate blades. Sori 
roundish, each borne on the back of a vein. Indusium membranous, hood-like, attached 
by a broad base on its inner side and partly under the sorus, early opening and somewhat 
evanescent. Veins free. ICystopteris Bernh,] 

Leaf-blades scarcely broader at the base, short-pointed, without bulblets. 1. F.fragilis. 

Leaf-blades broadest at the base, long-tapering, bearing bulblets beneath. 2. F. bulbifera. 

1. Filix fr^gilis (L. ) Underw. Leaves tufted ; petioles 10-20 cm. long ; blades thin, 
oblong-lanceolate, slightly tapering below, 1-3 dm. long, 2-3-pinnatifid or pinnate ; leaf- 
lets lanceolate-ovate, irregularly pinnatifid, with a broad central space and bluntly or 
sharply toothed segments decurrent along the margined or winged rachis, without bulb- 
lets : indusia narrow or acute at the free end, early withering. 

On rocks and in moist grassy woods, Newfoundland to Alaska, south to Georgia and Arizona. 
Almost cosmopolitan. 

2. Pilix bulbifera (L.) Underw. Leaves weak; petioles 10-15 cm. long, light- 
colored ; blades elongated, lanceolate from a broad base, 3-8 dm. long, 2-3-pinnatifid or 
pinnate ; leaflets crowded, toothed or pinnatifid : rachis wingless, commonly bearing under- 
neath, in the axils of the leaflets and segments, fleshy bulblets which fall away and propa- 
gate the plant : indusia truncate on the free side, early thrown back and withering. 

On moist rocks, especially limestone, Quebec to Wisconsin, south to Tennessee and Arkansas. 

30. WOODSIA R. Br. 

Small or medium-sized ferns, growing in rocky places. Leaves often evergreen, 
tufted : petioles often jointed above the base and finally separating : blades 1-2-pinnate or 
pinnatifid. Sori round, borne on the backs of simply forked free veins. Indusia inferior, 
thin and often evanescent, roundish or stellate, either small and open or early bursting at 
the top into irregular lobes or segments. 

Indusium minute or evanescent, flat, concealed beneath the sorus, its margin cleft into hair-like seg* 
ments. .^ , , ^ , , , ^ 1. TT. llvenm. 

Indusmm manifest, at first enclosing the sporanges, splitting into jagged lobes. 2. W, ohiusa, 

1. "Woodala HvSubIs (L.) K. Br. Leaf -blades lanceolate, 10-25 cm. long, glabrous 
above, more or less covered with rusty chaff beneath, as are also the slender jointed peti- 
oles ; leaflets crowded, sessile, pinnately parted, the crowded segments oblong, obscurely 
crenate : sori borne near the margins of the segments, somewhat confluent when old : in- 
dusium minute, concealed beneath the sorus, its margin cleft into filiform segments, which 
are inflexed over the sporanges and inconspicuous, especially when mature. 

. . On exposed rocks Labrador and Greenland to Minnesota, south to North Carolina and Kentucky. 
Also m Europe and Asia. 



2. Woodsia obtusa (Spreng.) Torr. Petioles not jointed, pale green, 7-15 cm. 

; leaf-blades broadly lanceolate, 15-40 cm. long, minutely glandular-pubescent, nearlv 

nnate ; leaflets rather remote, triangular-ovate, or oblong, pinnately parted into obtuse 

ate-dentate segments : veins forked, bearing the sori near the minutelv toothed lobes : 



inausia conspicuous, at hrst enclosing the sporanges, at length splitting into several lobe*. 

_ On rocks, Nova Scotia to New York and British Columbia, south to middle Georgia Texas and 

Arizona. . ' 



MARSILEACEAE 



19 



Order 3, SALVINIALES. 

Aquatic or mud-inhabiting herbs, with horizontal or creeping stems, or float- 
ing. Leaves various, sometimes filiform, or blades entire, lobed or 4-foliolate. 
Spores of two kinds (microspores and macrospores), contained in sporocarps. 
Macrospores germinating into simple prothallia which bear archegones, the 
microspores forming still simpler prothallia bearing antherozoids. 

Plants rooting in the mud : leaves filiform or with 4-foliolate blades. Fam. 1. Maksileaceae. 

Plants floating : leaves with entire or 2-lobed blades, Fam. 2. Salviniaceae. 



Family 1. MARSILEACEAE R. Br. Marsilea Family. 

Perennial herbaceous plants rooting in mud, with slender rootstocks. Leaves 
with 4-foliolate blades, or merely filiform. Asexual propagation consisting of spor- 
ocarps borne on peduncles which arise from the rootstock near the leaf-stalk, or 
are consolidated with it, containing both macrospores and microspores. 

Sporocarps ovoid : leaves with 4-foliolate blades. 
Sporocarps globose : leaves filiform. 



1. Marsilea. 

2. PiLULARIA 



1. MARSILEA L. 



Marsh or aquatic plants. Leaves commonly floating on the surface of shallow water ; 
blades slender-petioled, 4-foliolate. Peduncles shorter than the petioles, arising from 
their bases or more or less adnate to them. Sporocarps ovoid or bean-shaped, composed of 
two vertical valves with several transverse compartments (sori) in each valve, 

1. if. macropoda. 



Sporocarps 2-6 on each peduncle : leaves pubescent on both sides. 
Sporocarps solitary or rarely 2 on each peduncle. 

Leaflets 4-16 mm. broad, obovate or nearly obcordate. 
Sporocarps 3-5 X 4-7 mm.; raphe short, with acute teeth. 
Sporocarps 6X8 mm.; raphe long, with long hooked teeth. 
Leaflets 2-4 mm. wide, more or less falcate. 



2. M, vfstita, 

3. M. uncinata, 

4. M, tenuifolia. 



1. Marsilea macropoda Engelm. Plant robust, 10-25 cm. tall. Leaflets 2-5 cm, 
long, 2 cm. wide, or narrower, usually undulate, pubescent with white hairs on both sides, 
especially so when young: sporocarps 2-6 on erect branching peduncles, densely villous, 
6-8 mm. long, 5-6 mm. thick : raphe short, the lower tooth obtuse, the upper prominent 
or wanting : sori 10 in each valve. 

In muddy places, Texas and New Mexico. 

2. Marsilea veatita Hook. & Grev. Rootstock slender. Petioles 5-13 cm. high : 
leaflets entire or toothed : sporocarps 4-8 mm. long, 4-6 mm. wide, with a short raphe, 
a short and blunt lower tootn and an acute and sometimes curved upper one, densely cov- 
ered with soft spreading narrow hair-like scales, or in certain forms these are short and 
appressed or almost wanting : sori 6-11 in each valve. 

In wet sand or in shallow ditches. Kansas to British Columbia, Mexico, Texas and Florida. 

3. Marsilea uncinita A. Br. Plant 6-20 cm. tall. Leaflets nearly glabrous, entire, 
10-16 mm. wide, 8 mm. long : peduncles 15-30 cm. long, 2-4 times the length of the 
sporocarps : raphe long, terminating in 2 approximate teeth, the upper longer and mostly 
uncinately curved : sori 13-14 in each valve. 

In swamps, Louisiana and Texas. 

4. Marsilea tenuifolia Engelm. Plant slender, 5-15 cm. high. Leaflets 2-4 mm. 
wide, more or less falcate, often slightly truncate and unequally toothed at the apex, ap- 
pressed-pubescent : sporocarps solitary, 5-8 mm. long, 4-5 mm. wide, the teeth nearly 
equal, divergent : sori 9-12 in each valve. 

On borders of ponds, Pierdenales, Texas. 

2. PILULARIA L. 

Marsh plants with slender creeping rootstocks and few filiform leaves. Sporocarps 
globose, longitudinally 2-4-celled, dehiscing from the apex : cavities with parietal cushions 
bearing microsporanges above and numerous macrosporanges below. Macrospores solitary. 

Americana A. Br. Leaves filiform, about 2.5 cm. long. Sporocarps 
V nttaphpH hv thp sidp to a short descendinsr neduncle. 3-4-cellea : micro- 



Pilularia 



spores 



^ 



pools 



20 



EQUISETACEAE 



Family 2. SALVINIACEAE Reicheub. Salvinia Family. 

Small floating plants, with a more or less elongated and sometimes branch- 
ing axis bearing apparently 2-ranked leaves. Sporocarps soft, thin-walled, 
borne 2 or more on a common stalk, 1 -celled, with a central often brauclied re- 
ceptacle, which bears macrosporanges containing a single macrospore or micro- 
sporauges containing numerous microspores. 

1. AZOLLA Lam. 
Minute moss-like reddish or green floating plants, with pinnately branched stems cov- 
ered with minute imbricated 2-lobed leaves, and emitting rootlets beneath. Sporocarps of 



two kinds borne in the axils of the leaves, the smaller ovoid or acorn-shaped, containing 



a single macrospore at the base and a few minute bodies above it^ the larger globose, pro- 
ducing many pedicelled sporanges, each containing several masses of microspores. 

1. AzoUa Carolini^na Willd. Plants greenish or reddish, 2-4 mm. broad, deltoid 
or triangular-ovate, pinnately branching, sometimes covering large surfaces of water. 
Macrospores minutely granulate, with three accessory bodies ; masses of microspores 
armed with rigid septate processes : leaves with ovate lobes, their color varying with the 
amount of sunlight, the lower usually reddish, the upper green Avith a reddish border. 

Floating on still water. Ontario to British Columbia, south to Florida, Arizona and Mexico. 

Order 4. EQUISETALES. 

1 

Eush-like perennial plants, with horizontal rootstocks and mostly hollow 
jointed simple or often much -branched grooved stems, provided with a double 
series of cavities and usually with a large central one, the branches whorled, the 
nodes provided with diaphragms. Leaves reduced to toothed sheaths at the 
joints. Sporanges 1-celled, clustered underneath the scales of terminal cone- 
like spikes. Spores uniformj furnished with 2 narrow appendages (elaters) at- 
tached at the middle, coiling around the spores when moist, and spreading, when 
dry, in diverse ways. Prothallia terrestrial, green, usually dioecious. 



Family 1. EQUISETACEAE Michx. Horsetail Family 



Characters of the order. 

The'only genus. 



1. EQUISETUM L. 



Stems annual, of 2 kinds; fertile vernal, simple, soon withering; sterile much branched: stomata 

scattered. 1. E. arveiise. 

Stems perennial : spikes rigid-pointed : stomata in regular rows. 
Stems rough and tuberculate, prominently ridged. 

' Stems stout : ridges with 1 hne of tubercles : sheaths with 3-keeled lidges. 2^ E, robustum. 

■ Stems slender : ridges with 2 indistinct lines of tubercles : sheaths with obscurely 

4-keeled ridges. , 8. £. hyemale. 

Stems not tuberculate : sheaths enlarged upward. 4. EAaevigatum. 

1. Equisetum arv^nse L. Stems annual, with scattered stomata, the fertile appear- 
ing in early spring before the steriie. Fertile stems 1-2.5 dm. high, not branched, soon 
withering, light brown, their loose scarious sheaths mostly distant, whitish, ending in about 
12 brown acuminate teeth; sterile stems green, rather s'lender, 0.5-6 dm. high, 6-19-fur- 
rowed, with numerous long mostly simple whorled 4-angled or rarely 3-angled solid 
branches, their sheaths 4-toothed, the stomata in two rows in the furrows. 

In sandy soil. Newfoundland, Greenland and Alaska, south to North Carolina and California. Also 
in Europe and Asia.— £. an^eme serotmum is an occasional form with a cone terminating the normally 
sterile plant. Spring. Horsetail. 

2. Equisetum robtistum A. Br. Stems perennial, stout, tall, evergreen, 1-2.5 m. 
high, sometimes 2 cm. in diameter, 20-48-furrowed, simple or little branched. Kidges 
roughened with a single series of transversely oblong siliceous tubercles : sheaths short, 
cylindric,*appressed, marked with black girdles at the base, and at the bases of the dark 
caducous teeth ; ridges of the sheath 3-carinate ; branches, when present, occasionally 
fertile : spikes tipped with a rigid point. 

In wet places, Ohio to British Columbia, south to Louisiana, California and Mexico. Also in Asia. 

3. Equisetum hyemale L. Stems slender, rather stiff, evergreen, 6-12 dm. high, 
with the stomata arranged in rows, rough, 8-34-furrowed, the ridges with two indistinct 






LYCOPODIACEAE 



21 



lines of tubercles, the central cavity large, from one-half to two-thirds the diameter ; 

sheaths rather long, cylindric, marked with one or tAVo black girdles, their ridges obscurely 

4-keeled ; teeth brown, membranous, soon deciduous : stem rarely producing branches 

Avhich are usually short and occasionally fertile, sometimes with longer sterile branches. 

In wet places, especially on river banks, widely distributed in North America, Europe and Asia. 
Scouring Rush. 

4. Equisetum laevigktum A. Br. Stems 3-15 dm. high, simple or little branched, 
pale green, persistent, 14-30-furrowed, the ridges almost smootli. Sheaths elongated and 
enlarged upward, with a black girdle at the base of the mostly deciduous, white-margined 
teeth and rarely also at their bases ; ridges of the sheath with a faint central carina and 
sometimes with faint short lateral ones : stomata arranged in single series ; central cavity 
verv laro^e, the wall of the stem verv thin. 

Along streams, especialjy in clay soil, New Jersey to British Columbia, south to North Carolina, 
Louisiana and California. • 

Order 5. LYCOPODIALES. 

Terrestrial or epiphytic plants with spores produced in sporanges borne in 
the axils of scale-like leaves. 

Spores all of one sort and size. • 

Sporanges 1-celled, transversely 2-valved : stems leafy. Fam, 1. Lycopodiaceae. 

Sporanges 2-3-celled, opening by 2-3 apical valves : stems and branches 

nearly naked. Fam. 2. Psilotaceae. 

Spores of two sizes, macrospores and microspores. Fam. 3, Selaginellaceae. 



Family 1. LYCOPODIACEAE Michx. Club-moss Family. 



Mos 



Leaves often nu- 



merous, in 2-several series : blades narrow. Sporanges 1-celled, solitary in the 
axils of leaf-like or scale-like bracts (sporophylls), sometimes forming compact 
cones (strobiles). Spores uniform, minute. Prothallia (as far as known) mon- 
oecious, mostly subterranean. 

1. LYCOPODIUM L.i 

Perennial evergreen plants various in habit. Leaves in 4-16 series : blades 1-nerved. 
Sporanges 1-celled, in the axils of more or less distant leaf-like bracts or collected into ter- 
minal compact bracted cones, transversely 2-valved. Spores of one kind, sulphur-yellow, 
copious, readily inflammable. Some species are known as Club-mosses. 

Plants with mostly upright stems: leaves and bracts (sporophylls) in alternating zones (cones inter- 
runted). 
Leaf-blades appressed, with hollow bases. 1. L, Selago, 

Leaf-blades ultimately reflexed, flattened at the bases. 

Leaf-blades linear or nearly so, entire or denticulate. 2. Z. porophilum. 

Leaf-blades manifestly broadest above the middle, erose. 3. i. iucidulum. 

Plants with creeping or horizontal stems (rootstocks): cones terminal. 
Sporanges globose : bracts and leaves similar. 

Bracts 5-6 mm. long, often slightly toothed at the base. 4. L. Chapmanu 

Bracts 8-10 mm. long, usually much toothed. 

Leaves in many series, radially spreading : stems arching. 5. X. alopccuroides. 

Leaves twisted so as to be in one plane : stems prostrate. 6. X. pinnatiim. 

Sporanges transversely compressed, reniform : bracts entirely unlike the leaves. 

Stems (rootstocks) prostrate or creeping : leaves nearly in one plane, 7. X. Caroliniamim . 

Stems (rootstocks) creeping or horizontal, with erect or ascending branches. 
Leaves equal, radially arranged (except on twigs of No. 8), in 5 or more series. 

Cones few, stout, erect. 8. X. ohseurum. 

Cones numerous, short, nodding. 9. X. ceimuum. 

Leaves dorsiventrally arranged in 4 series on flattened stems. 

Leaves of under row scarcely reduced : terminal branches erect. 10. L, tristachijum. 

Leaves of under row reduced to subulate scales : terminal branches 

horizontally fan-like. 11. X. complanatum. 

1- Lycopodium Sel^go L. Prostrate portion of the stems very short, rooting, curv- 
ing upward, thence dichotomonsly branched and forming tufts 4-17 cm. tall. Leaves densely 
disposed, appressed or ascending; blades triangular, linear-subulate or subulate, 4-8 mm. 
long, broadest at the hollow base, entire : bracts shorter than the leaves, triangular : 

sporanges reniform. 

On rocks and shaded cliffs, Labrador, Greenland and Alaska, south to Maine. Michigan and Wash- 
ington and on the mountains to North Carolina. Also in Europe and Asia. 

2. Lycopodium porophilum Lloyd & Underw. Prostrate portion of the stems short, 
abundantly rooting, curving'upward, thence forking 1-3 times and forming tufts 4-10 cm. 
talL Leaves densely disposed, spreading or reflexed ; blades very slightly broadened 

^ Revised by Prof. Francis Ernest Lloyd. 



/ 



22 LYCOPODIACEAE 



above tlae middle and somewhat contracted near the base, those between the sporangial re- 
gions 6-7 mm. long, broadest at the base, entire or denticulate : sporanges reniform : bracts 
(sporophylls) 4-5 mm. long, denticulate or entire, acuminate. 

On sandstone cliffs, Wisconsin, Indiana, Kentucky and Alabama. 

3. Lycop odium lucldulum Michx. Prostrate portion of the stems 5-15 cm. long, 
rooting, thence usually forking 1-3 times, forming lax clusters 1-3 dm. tall. Leaves 



numerous, reflexed ; blades linear-spatulate, 8-11 mm. long, acute, erose-denticulate, 1 mm. 
wide at the base : bracts linear to lanceolate, 3.5-8.5 mm. long, sometimes denticulate: 
sporanges depressed-reniform. 

In cool woods and on damp slopes, Newfoundland to British Columbia, south to South Carolina, 
Tennessee and Iowa. 

4. Lycopodium ChapmdniiUnderw. Stems creeping or arching, about 3 mm. thick, 
18-40 cm. long, simple or occasionally pinnately branched. Leaves numerous ; blades 
lanceolate, 6-7 mm. long, acuminate, curved upward, irregularly toothed, with the lower 
teeth often branched, or those of the fertile branches appressed, the lower with subulate 
teeth, upper entire : fertile branches 10-25 cm. long : cones 1.8-7 cm. long, or sometimes 
longer, about 3 mm. thick : bracts 5-6 mm. long, toothed just above the base, whence they 
are contracted into subulate tips : sporanges nearly globular. 

In sandy bogs, Massachusetts to Florida and Louisiana. 

5- Lycopodium pinnktum (Chapm. ) Lloyd & Underw\ Stems 20-30 cm. long, pin- 
nately branched, 1-2 mm. thick. Leaves numerous ; blades thin, 8-9 mm. long, linear- 
lanceolate, curved, long-toothed, those of the upper side of the stem smaller, all slightly 
contracted at the base : fertile branches 25-40 cm. long, their numerous leaves narrower 
than the stem-leaves : cones 3-12 cm. long, 5 nmi. thick : bracts spreading, similar to the 
leaves of the fertile branches but more gradually tapering : sporanges nearly globular. 

In low sandy grounds, southern Georgia, Florida and Alabama, 

6. Lycopodium alopecuroides L. Stems 5 dm. long, or even longer, arching, root- 
ing at the ends. Leaves numerous ; blades 5-7 mm. long, lanceolate, and spinulose on the 
sides of the stem, linear-lanceolate and long-toothed on the upper and lower sides of the 
stem, and with long hairs near the base on the lower side of the stem ; fertile branches 
2-3 dm, tall, densely leafy, resembling the stem; cones 2-10.5 cm. long, 5 mm. thick: 
bracts 10-11 mm. long, becoming reflexed, similar to the leaves of the fertile branches but 
not hairy. 

In low pine lands, Long Island to Florida and Mississippi, usually within about 125 miles of the 
coast. Also in Brazil. 

7. Lycopodium Caroliniknum L. Stems prostrate or creeping, 1-15 cm. long, 1- 
1.5 mm. thick, pinnately branching. Stem-leaves of 2 kinds, the apparently lateral ones 
ovate-lanceolate, 5-6 mm. long, falcate, recurved, acute, entire, with the midrib asymmetri- 
cally placed ; leaves of the upper side of the stem 3-4 mm. long, subulate above the broad 
base : fertile branches slender, 5-22 cm. tall, their leaves few, subulate, 2-3 mm. long, ap- 
pressed : cones 1-5 cm, long, 2-2.5 mm. thick : bracts triangular, or somewhat constricted 
above the base, sometimes erose : sporanges compressed. 

In sandy bogs, New Jersey to Florida and Mississippi, Also in tropical America. 

8. Lycopodium obscurum L. Stems or branches arising from horizontal root- 
stocks, becoming bushy and 1-3 dm. tall. Leaves ntimerous, spreading and curved up- 
ward ;^ blades linear-lanceolate, mucronulate, in 8 rows below, in 6 rows above, twisted so 
a^ to lie in vertical planes : cones sessile : bracts broadly ovate, papery, erose, subulate- 
tipped ; sporanges reniform. [L. dendroideum Michx. ] 

In woods, Newfoundland to Alaska, south on the mountains to Georgia, and Montana. Also appar- 
ently in Japan. Ground Pine. 

9. Lycopodium c^muxun L. Stems procumbent or arching, 2-3.5 dm. long, some- 
what creeping, branching, often in various planes, the ultimate branches nodding and 
fertile. Leaves numerous, terete, subulate, 3-5 mm. long, spreading and upwardly curved : 
cones sessile, 5 mm, long: bracts ovate, acuminate, thin-fringed : sporanges minute, trans- 
versely flattened. , 

In sandy soil or pine lands, Florida to southern Mississippi. Also in tropical regions. 

10. Lycopodium tristAchyum Pursh. Rootstocks horizontal ; branches becoming 

erect, or decumbent, repeatedly forking to form several vertically placed flattened branch- 
lets 1.5-2 mm. wide. Leaves of branches appressed or incurved ; blades linear-subulate : 
fertile branches scape-like, 5-6 cm. tall, usually twice-forked : cones 2, 3 rfr casually 4, 2-2.8 
cm. long: bracts ovate, abruptly subulate-tipped. [L. Chamaecyparissus A. Br.] 

In woods, Maine to Minnesota, south along the mountains to North Carolina. ' ■ 

11. Lycopodimn complanktum L. Rootstocks creeping ; branches erect, repeatedly 
forked to form several horizontally spreading branchlets, 1.8-2.5 mm. wide. Leaves of 



SELAGINELLACEAE 23 

branches somewhat spreading, linear, with subulate tips : fertile branches erect, 5-8 cm. 
long, usually twice-forked : cones 15-25 mm. long: bracts ovate, gradually contracted to 
the subulate tips, toothed. 

In woods, Prince Edward Island to Ontario and Minnesota, south to the mountains of North Caro- 
lina. Also in Europe and Asia. Christmas-green. 

Family 2. PSILOTACEAE Pritzel. Psilotum Family. 

Perennial slender terrestrial or epiphytic plants. Sporanges sessile in the 
axils of the leaves, 2-3-celled, opening by valves at the apex. Spores uniform. 

1. PSILOTUM R. Br. 

Terrestrial or sometimes epiphytic. Stem dichotomously forked. Leaves alternate, 
reduced to scales. Sporanges 3-celled, opening by 3 valves at the apex. Spores mealy, 
oval or elongated-reniform. 

1. Psilotum nudum (L.) Griseb. Stems erect, 20-25 cm. tall, 3-angled at the base, 
copiously forked above, the ultimate divisions with 3 wing-like angles : leaves remote, 
awl-like, 1-1.5 mm. long : sporanges in interrupted spikes. [P. iriquetrum Sw.] 

In hammocks, South Carolina to Florida. Also in tropical America. 

Family 3, SELAGINELLAcEAE Underw. Selaginella Family, 

Terrestrial moss-like annual or perennial plants, with much branched stems. 
Leaves scale-like, uniform and several-ranked, or of 2 kinds and in 2 planes, 
Sporanges 1-celled, disposed in 4-sided cones, solitary in the axils of bracts, 
some containing 4 macrospores (macrosporanges), others containing numerous 
microspores (microsporanges), which develop into small prothallia, those from 
the macrospores bearing archegoneSj those from the microspores antherids. 



1. SELAGINELLA Beauv. 



Characters of the family. 



1. S. apus. 



3. S, arenicola. 



stem-leaves of 2 kinds, spreading in two planes, 
stems flaccid, creeping; microspores warty. 

stems rigid, ascending; microspores smooth. 2. S. Ladoviciana. 

Stem-leaves all alike, several-ranked. 

Stems erect or ascending, « 

Cones 2-3 cm. long, slender. 
Cones 5 mm, long or less, as stout as the diameter of the stem. 4. S. Skerwoodii, 

Stems spreading or creeping. 

Stems rooting only near the base : leaves with tortuous hairs. 5. 5. tortipila. 

Stems rooting throughout, usually less than 1 dm. long : cones 10-15 mm, long ; 
leaves ending in a slender awn. 
Lips of the dorsal groove of the leaf-blades glabrous. 6. S. rupestria. 

Lips of the dorsal groove of the leaf-blades spinose-ciliate. 7. S, acanthonota. 

1. Selaginella ^pxis (L. ) Spring. Annual, pale green. Stems creeping, 5-15 cm. 
long, flaccid, pinnately branched : leaves in two planes, those of the lower plane ovate, 
acute, short-ciliate on the margins, those of the upper plane lanceolate short bristle-pointed : 
cones 6-15 mm, long, obscurely 4-angled: bracts ovate, acutely keeled above : microspores 
warty. 

In moist shaded ground, Maine and Ontario to the Northwest Territory, Florida and Texas. 

2. Selaginella Ludovlci^a A.Br. Annual, dark green. ^ Stems creeping or ascend- 
ing, 15-30 cm. long, once or twice pinnately branched : leaves in two planes, those of the 
lower plane broadly ovate, obtuse, with whitish margins formed of sclerotic cells, those of 
the upper plane lanceolate with slender acuminate tips : cones 1-2 cm. long : micro- 
spores smooth. 

In shaded ground, Florida to Louisiana. 

3. Selaginella arenicola Underw. Roots copious, delicate, 15-20 cm. long. Stems 
much branched, the branches tufted, slender, 5-8 cm. tall, giving off brown roots near 
their bases: leaves appressed, narrowly lanceolate, 0.25 mm. wide, ciliate, channeled dor- 
sally, tipped with a gpinulose white awn 0.35-0.50 mm. long: cones sharply 4-angled, 2-3 
cm, long : bracts broadly lanceolate, spreading, with 15-20 cilia on each side : micro- 
spores copious, globose-tetrahedral. 

In exposed sandy fields, Georgia and Florida. 

4. Selaginella Sherwoddii Underw. Plants forming densely branched compact 
tree-like tufts 6-8 cm. high. Stems repeatedly branching, erect or ascending, rooting only 
at the base, rigid ; leaves about 10-ranked, about 1.5 mm. long, closely appressed, grooved 



24 



ISOETACEAE 



dorsally in the lower two thirds, ending in a slender white coiled hair 0.7-0.9 mm. long^ 
and with 8-12 minute cilia on each margin ; cones less than 5 mm. long, terminal on the 
branches, the sporophylls similar to the ordinary leaves ; macrosporangia three-lobed, the 
macrospores pale yellow, rugose-reticulate, 0.44 mm. in diameter ; microsporangia round- 
reniform, the microspores bright yellow, smooth, 44 u in diameter. 

On rocks, mountains of southwestern North Carolina. 

5. Selaginella tortipila A. Br. Stems rooting only near the base ; branches] zigzags 
20-25 cm. long, primary ones elongated. Leaves about 6- ranked, loosely imbricated, 
narrowly lanceolate, ciliate, scarcely channeled, tipped by a contorted or coiled hair : cones 
4-5 mm. long, slightly 4-angled : bracts ovate-lanceolate, loosely spreading, dorsally 
channeled. 

On rocky mountain tops, North Carolina and South Carolina. 

6. Selaginella rup6stris (L. ) Spring. Stems and branches creeping, 5-10 cm. long, 
zigzag, ascending at the tips ; primary branches short. Leaves closely imbricated, about 8- 
ranked, 0.3-0.38 mm. wide, deeply clianneled dorsally, with 6-9 cilia on each side, 
tipped with a white spinulose awn about 1 mm. long : cones 1-1.5 em. long, sharply 4- 
angled : bracts similar to the leaves but broader and with shorter awns and more cilia. 

On dry rocks, Maine and Ontario to British Columbia, south to Georgia and Missouri. 

7. Selaginella acanthonota Underw. Stems and branches stout, rooting and ascend- 
ing, softly plumose at the tips. Leaves of the stems in 8-10 regular series ; blades about 
2 mm. long, gradually tapering into a roughened awn one-half to one-third their length, 
with about 12 short irregular cilia on each side and similar cilia on either side of the dorsal 
groove : cones fully 10 mm. long : bracts broadly triangular, ciliate like the leaf-blades. 

In sand, near the coast, North Carolina. Summer. 

Order 6. ISOETALES. 

Submerged, amphibious or uliginous plants, with a cluster of elongated awl- 
shaped leaves rising from a more or less 2-3-lobed fleshy short stem, the leaves 
with or without peripheral bast-bundles, with or without stomata, bearing a 
small membranous organ (ligule) above the base. Sporanges sessile in the ex- 
cavated bases of the leaves, the sides more or less covered with a fold of the 
inner side of the leaf-blades (velum) ; those of the outer leaves usually contain 
spherical, mostly sculptured macrospores, those of the inner contain minute 
powdery oblong microspores ; the former germinate into prothallia bearing only 
archegones, the latter into prothallia bearing usually only a single antherid. 

Family 1. ISOETACEAE Horan. Quillwort Family. 



Characters of the order. 



1. ISOETES L. 



The only genus. Owing to their aquatic habitat and apparently local distribution, 
these plants are popularly little known. Some species are called Quillwort. 

Velum incomplete or wanting. 

Amphibious : macrospores honeycombed-reticulated, 1. J. EngelmanniL 

Terrestrial : macrospores tuberculate. 

Polygamous : leaves 1^-60, often blackish at the base. 2. J. melanopoda. 

Dioecious : leaves 8-15, bright green. 3. /, Butleri. 

Velum complete. 

Macrospores dark-colored : leaves 5-6 cm. long. 4, /. melaiiospora, 

Macrospores light-colored : leaves 40-60 cm. long. 5. Lflaccida. 

1. Isoetes Engelxn^nnii A. Br. Amphibious, usually partly immersed when mature. 
Leaves 25-100, liglit green, quadrangular, tapering, 22-50 cm. long, bearing abundant 
stomata : peripheral bast-bundles present : sporanges oblong or linear-oblong, unspotted : 
velum narrow : macrospores 400-520 /x in diameter, covered with honeycomb-like reticula- 
tions : microspores 24-28 // long, mostly smooth. 

In ponds and ditches, rooting in mud, Maine to Delaware, Pennsylvania and Missouri.— Repre- 
sented in our range by /. Engehnannii Georgldna Engrelra., which has fewer leaves and slightly larger 
macrospores, and is known from Georgia ; and by 7. Engelmannii CaroUnidna A. A. Eaton, which has 
stouter leaves, a broader velum and larger brown densely muricate microspores; it occurs in the 
mountains and middle country of North Carolina. 

2. Isoetes melanopoda J. Gay. Terrestrial, with a subglobose deeply 2-lobed trunk. 
Leaves 15-60, slender, erect, bright green, with a blackish shining base, 12-15 cm. long, 
3-angled, bearing stomata throughout, and well developed peripheral bast-bundles ; ligule 



ISOETACEAE 



25 



3-angled, awl-shaped : sporanges mostly oblong, spotted, witli a narrow velum : polyga- 
mous : macrospores 250-400// in diameter with low more or less confluent tubercles, often 
united into worm-like wrinkles, or almost smooth : micros})ores 23-28 // long, spinnlose. 

On moist prairies and in overflowed fields, Iowa to Illinois, Missouri and Texas,— The Texan form 
has larger leaves with pale bases. 

3. Isoetes Biitleri Engelm. Terrestrial, from a subglobose trunk. Leaves 8-15, 
bright green, paler at base, triangular, 4.5-18 cm. long, bearing numerous stomata, and 
with well developed peripheral bast-bundles, thick dissepiments and small air cavities : 
sporanges usually oblong, spotted : velum very narrow or none : ligule small, triangular: 
dioecious ; macrospores 500-630 /i in diameter, with distinct or confluent tubercles. 

On rocky hillsides, Missouri and Indian Territory.— A variety, 7. Butlcn iramac aldta Engelm., grow- 
ing in the barrens about Nashville, Tennessee, has longer leaves, unspotted sporanges and spinulose 
microspores. 

4. Isoetes melandspora Engelm. Stem ilat, slightly 2-lobed. Leaves 5-10, dis- 
tichous, slender, 5-6 cm, long, light green : sporanges orbicular or nearly obcordate, 1-2 
mm. long, covered by the velum : ligule triangular, obtuse: macrospores 350-450 /i long, 
with distinct or confluent warts, dark-colored : microspores 28-31 fi long. 

In shallow excavations in granite, slopes and summit of Stone Mountain and Little, Stone Moun- 
tain, middle Georgia. 

5. Isoetes fldccida Shuttlw. Leaves 10-35, light green, 4-6 dm. long, submersed or 
emersed. Sporanges oval, 4-6 mm. long, covered with numerous, or rarely few large flat- 
tish tubercles, these distinct or confluent into labyrinthiforra wrinkles. 

In lakes and ponds, western and peninsular Florida. — A variety, Lflacdda rigida Engelm. from 
Lake Flirt, is smaller, and has more slender and erect leaves. 

SuBKiNGDOM SPERMATOPHYTA. Seed-bearixg Plants. 

Plants producing seeds each of which contains an embryo consisting of 
a short stem (radicle^ caulicle or hypocotyl), one, two or several rudi- 
mentary leaves (cotyledons) and a terminal bud (plumule). These parts 
are sometimes partially undifferentiated before germination. Microspor- 
anges (anther-sacs) are borne on modified leaves (filaments) and contain 
usually several or many microspores (pollen -grains). Macrosporanges 
(ovules) are borne on the surface of a flat or inroUed modified leaf (car- 
pel) and contain a macrospore (embryo-sac). A macrospore develops the 



lum 



lium 



tube) 



ium Drotrudiner from 



Ovules and seeds borne on the face of a bract or a scale : stigmas wanting. Class 1. Gymnospermae. 
Ovules and seeds in a closed cavity (ovary): stigmas present. Class 2. Angiospermae. 

^ ■ 

Class 1. GYMNOSPERMAE. 

Carpel or pistil represented by a scale or disk upon whose face are 
borne the ovules (macrosporanges). Pollen-grains (microspores) divide 
into two or several cells, one of which gives rise to the pollen-tube (male 
prothallium) ; a sperm-cell or spermatozoid developed at the end of a 
pollen-tube directly fertilizes an egg-cell in the archegone of the embryo- 
sac (female prothallium) in the ovule (macrosporange). 

Order 1. CYCADALES. 

Relatively low palm-like plants. Stems scarred with the bases of fallen 
leaves. Leaves aggregated in a terminal crown : blades pinnate. Flowers in 
terminal or nearly terminal cones of often numerous approximate scales, or on 
slightly modified leaves. Staminate cones with peltate or boat-shaped scales 
supporting several pollen-sacs. Pistillate with two or more ovules on each flat 
or shield-like scale. Seed drupe-like or nut-like. 



f T 



26 



PIXACEAE 



Family 1. CYCADACEAE LiudL Cycas Family. 

Shrubs or trees of tropical or subtropical regions, usually possessing a sticky 
sap. Leaves (fronds) clustered : blades pinnate : segments variously nerved. 
Flowers dioecious, without perianth : staminate cones falling away : pistillate 
leaves or cones accrescent. Pollen-sacs 1-celled, in groups of 2-4, or more. 
Ovules orthotropous, sessile or nearly so. Fruit an aggregate of nut-like or 
drupe-like seeds. Embryo in the upper part of the endosperm. Cotyledons 2 ; 
radicle ending in a spiral. ^ 

1. ZAMIA L.i 

Usually low palm-like plants, with stems usually beneath the surface of the ground. 
Leaves few or many : blades pinnate : petioles smooth or spiny ; segments with simple par- 
allel nerves, entire or toothed, jointed at the rachis. Flow.ers in oblong or cylindric cones : 
scales peltate, spirally arranged. Pollen-sacs numerous. Ovules 2 on each scale, pendu- 



lous, sessile. Cones relatively small, glabrous or scurfy, Coontik. 

Leaf-segments 10-16-nerved : mature pistillate cones 12-16.5 cm. long, markedly umbonate. 

1. Z. Floridana. 
Leaf -segments 20-28-nerved : mature pistiUate cones 6.5-10.5 cm. long, scarcely umbonate. 

2. Z. pumila, 

1. Zamia Floridana DC Plants 3—5 dm. tall. Leaf-blades ovate or ovate-lanceo- 
late, 20-30 cm. long ; petioles about 20 cm. long, unarmed, 3-angIed, silky tomentose at the 
base, with scattered hairs above: leaf-segments mostly opposite, 28-40, linear, 9-14 cm, 
long, 3-7 mm. broad, with 5 or 6 obscure teeth at the obtuse apex, glabrous above, with a 
few scattered hairs beneath, falcate and somewhat twisted, 10-16-nerved, revolute : stami- 
nate cones dark brown, oblong, about 8 cm. long and 2.5 cm. thick ; peduncles 5-10 cm. 
long: mature pistillate cones oblong, 12-16.5 cm. long and 6-8 cm. thick, markedly um- 
bonate, densely tomentose with persistent dark brown hairs, peduncles about 10 cm. long, 
ferruginous-tomentose : seed-bearing scales hexagonal, thick, nearly hemispheric at the 
outer end, [ Z, integrifolia Chapm, in part, not Jacq.] 

In dry forests, ** flat woods," east coast of Florida below New River. 

2. Zamia pumila L. Plants usually more robust than those of Z. Floridana, Leaf- 
segments mostly opposite but sometimes irregularly placed, 32-44, linear-oblanceolate or 
linear-oblong, somewhat falcate, 7-11 cm. long, 8-16 mm, wide, slightly serrate at the ob- 
tuse apex, mostly straight but occasionally slightly twisted, 20-28-nerved, revolute : stami- 
nate cones brown, oblong, about 8 cm. long and 2.5 cm. thick : peduncles 5-10 cm. long : 
mature pistillate cones elliptic, scarcely umbonate, 6.5-10.5 cm. long and 5-8 cm, thick, 
densely tomentose with ferruginous partially deciduous hairs: seed-bearing scales hexagonal, 
thin, somewhat flattened at the outer end. \_Z. integrifolia Chapm. in part, not Jacq.] 

In moist woods, ** hammocks," middle peninsular Florida, particularly on the eastern coast. 

Order 2. PINALES. 

Shrubs or lofty trees, various in habit. Leaves scale-like, narrow, or needle- 
like and often collected into bundles, or rarely with expanded blades. Flowers 
in cones of spirally imbricated scales, the staminate and pistillate usually on the 
same plant. Staminate cones with scales bearing pollen-sacs. Pistillate cones 
with scales bearing ovules : in Tax ace ae the pistillate flowers are rarely in 
cones. Fruit drupe-like, berry-like, or a dry cone. Embryo usually axile. 

Pistillate flowers several, with carpellary scales, these sometimes bracted: fruit a cone, either dry or 
berry-like. 
Carpellary scales with bracts, never peltate : ovules inverted : buds scaly : wing accompanying the 

seed a portion of the carpellary scale. Fam. 1. Pinaceae. 

Carpellary scales without bracts, mostly peltate or fleshy : ovules erect : 

buds naked : wing of the seed, whe"n present, a portion of the testa. Fam, 2. Juniperaceae. 
Pistillate flowers solitary or 2, without carpellary scales : fruit drupaceous or 

baccate. Fam. 3. Taxaceae. 

Family 1. PINACEAE Lindl. Pine Family. 

Mostly evergreen monoecious resin-yielding shrubs or trees, often conic in 
outline. Buds scaly. Leaves rigid, needle-like or flat, alternate, opposite, 
whorled, or several in a sheath. Anthers 2-several-celled, in more or less 
elongated cones. Pollen-grains globose, ellipsoidal or lobed. Pistillate aments 

^ Contributed by Mr. Herbert J. AVebber. 



PINACEAE 



27 



1. PiNUS. 

2. Carvopitys. 

3. Strobus. 



solitary or clustered, consisting of usually numerous spirally disposed bracted 
scales. Ovules in verted, usually 2 at the base of each scale. Fruit a dry cone 
formed by the accrescent scales of the pistillate aments. Seeds usually two at 
the base of each scale, often samara-like, the wing a portion of the carpellary 
scale. Endosperm copious, fleshy, or somewhat mealy. Cotyledons 2-16. 

Leaves several together, surrounded by a sheath at the base: cones maturing the second year. 
Cone-scales with dorsal usually spine-armed appendages : leaves mostly in 2's or 3's. 

Leaves with 2 fibro-vascular bundles : seeds with elongated wings, these free from the scales, and 

attached to the seeds when they fall. 
Leaves with 1 libro- vascular bundle : seeds with narrow or rudimentary wings, 
these adnate to the scales when the seeds fall. 
Cone-scales with inconspicuous terminal unarmed appendages : leaves in 5's. 
Leaves solitary, without a sheath : cones maturing the first year. 
Cones drooping : bracts shorter than the scales. 

Leaves 4-sided or nearly terete, spreading : anther-sacs opening lengthwise. 
Leaves flat, apparently 2-ranked : anther-sacs opening transversely. 
Cones erect : bracts longer than the scales. 

1. PINUS L. 

Kigid monoecious evergreen trees or rarely shrubs, of great economic importance. 
Leaves needle-like, 2-3 together or rarely more, each with 2 fibro-vascular bundles, the 
clusters surrounded at the base by a thin persistent sheath, spreading in all directions. 
Staminate aments elongated, at the ends of branchlets of the preceding year. Anthers 
2-celled, opening longitudinally. Pollen-grains of 3 cells, the 2 lateral cells empty. Pistil- 
late aments globose or slightly elongated, just back of the terminal bud, or on the young 

scales crowded. Cones maturing the second year : scales at length hard and spread- 
Seeds samara-like. The 



4. PiCEA. 

5. TsuoA. 

6. Abies. 



twigs 



2. P. ElliottiL 



3. P. Taeda. 

4. P. heterophylla 



ing, each appendaged below the apex, usually spine-tipped, 
plants flower in the spring. 

Scales of the pistillate aments stout, each with a short tip which scarcely equals the body in length. 
Cones over 7 cm. long. 

Cones 16-25 cm. long, the spines of the scales stout and strongly recurved : staminate aments over 

5 cm. long : seed-wing over 4 cm. long. 1. P. paluatris. 

Cones 8-14 cm, long, the spines of the scales small, not recurved : staminate 
aments less than 5 cm. long: seed-wing less than 4 cm. long. 
Leaves not glaucous : cone of an ovoid type when open, flat or depressed 

at the base : seed-wing 2.5-3 cm. long. 
Leaves glaucous : cones of a cylindric or conic-cylindric type when open, 
rounded at the base : seed-wing 1.5-2 cm. long. 
Appendage of the cone scale very thick at the apex, projecting littletif 

at all beyond the spine. 
Appendage of the cone-scale thin at the apex, projecting far beyond the 
spine. 
Cones less than 7 cm. long. 

Cones ovoid or globular-ovoid when closed : leaves 15-25 cm. long, about 2 
« mm. wide. 

Cones narrowly conic when closed : leaves 4-12 cm. long, about 1 mm. wide. 
Cone-scales readily opening, each with a slender or minute spine towards 
the front of the appendage, the spine sometimes deciduous or obsolete. 
Cones mainly less than 5 cm. long : scales of the staminate aments erose- 

toothed at the apex : baric of the trunk relatively close and smooth. 6. P. glabra. 
Cone mainly over 5 cm. long: scales of the staminate aments, entire : 
bark of the trunk very rough and shaggy. 
Cone-scales tardily opening or permanently closed, each with a'stout spine 
at the middle or towards tne back of the appendage. 
Scales of the pistillate aments slender, each with a subulate tip several times the 
length of the body. 
Cones conic when closed, ovoid when open : twigs glaucous. 
Cones ovoid when closed, globose-ovoid or depressed when open ; twigs vellow. 
Scales of the pistillate aments recurved : appendages of the cone-scales rela- 
tively thin ; spine slender, more or less recurved. 
Scales of the pistillate aments ascending : appendages of the cone-scales verj' 
thick ; spines stout, more or less incurved. 



5. P. serotina. 



7. P. echinata* 

8. P. clausa. 



9. P. Virginiana, 



10. P. rigida. 



11. P. pungeiis. 

1. Pinus paMstris Mill. A tree of great economic importance, reaching a lieight of 
40 m. and a maximum trunk diameter of 1.5 m., with few irregular spreading branches 
near the top, the bark separating into large thin plates. Leaves typically 3 in a sheath, 
20-40 cm. lorig, bright green, plumosely crowded at the tips of the branches, partially 
drooping: sheaths 2-3 cm. long : staminate aments 5.5-8 cm. long : cones 16-25 cm. long, 
narrowly conic when closed, broadly conic when open, often slightly curved, each scale 
armed with a stout recurved spine : seed 12-13 mm. long, the wing 4.5-5 cm. long. [P. 
dUBtralhWichx/] 

In sandy soil, southeastern Virginia to Florida and Texas, locally inland to the foothills of Georgia 
and Alabama. Georgia Pine. Ykllow Pine. Long-leaf Pine. 

2. Pinus Ellidttii Engelm. A tree resembling P. palustris in habit, but smaller. 
Leaves 2 or 3 in a sheath, 18-30 cm. long, bright green : sheaths about 1.5 cm. long : stami- 



o 



8 



PINACEAE 



nate aments 3.5-4 cm. long : cones 10-14 cm. long, broadly conic "when closed, ovoid M'hen 
open, straight, each scale armed with a small straight spine : seed 6-8 mm. long, the wing 
2-2.5 cm. long. 

In sandy, usually low pine lands, North Carolina to Florida and Mississippi. This species and the 
preceding furnish the turpentine of commerce. Slash Pine. 

3. Pinixs Tafeda L. A tree reaching a height of 46 m. and a maximum trunk 
diameter of 1.5 m., the bark dark, very rough, deeply furrowed, exfoliating in coarse 
plates. Leaves glaucous, 3 in a sheath, 15-28 cm. long : sheaths 15-20 mm. long : stami- 
nate aments 1.5-3 cm. long : cones 10-13 cm. long, narrowly conic when closed, cylindric 
or conic-cylindric when open, each scale with a thick appendage which projects little if 
at all beyond the small spine : seeds 6-7 mm. long, the wing usually about 2 cm. long. 

In sandy or clay soil, Delaware and Arkansas to Florida and Texas. Loblolly or Old-Field Pine. 

4. Pinus heterophylla (Ell. ) Sudw. A tree becoming 35 m. tall, with a maximum 
trunk diameter of 1 m., the bark pale, thick, but not deeply furrowed. Leaves glaucous, 
2 or 3 in a sheath, 12-25 cm. long: often stouter than 'those of P. Taeda: sheaths 1.5-2 
cm. long : staminate aments 1.5-2.5 cm. long ; cones 9-14 cm. long, narrowly conic when 
closed, cylindric or conic-cylindric when open, each scale with a thin appendage which pro- 
jects far beyond the slender spine : seeds 5-7 mm. long, the wing 2-2.5 cm. long. 

In swampy pine lands near the coast, South Carolina and Georgia. Pond Pine. Slash Pine. 

5. Pinus serotina Michx. A tree reaching a height of 25 m., with a maximum 
trunk diameter of 9 dm., the trunk clothed with a flaky bark and bearing many irregular 
short branches near the base. Leaves glaucous, 3 in a sheath, 15-25 cm. long, crowded : 
sheaths about 15 mm. long : staminate aments 1.5-2 cm. long : cones 4-6 cm. long, ovoid 
or globular-ovoid when closed, very broad when open, each scale with a thick appendage 
and a minute spine : seeds 3-4 mm. long, the wing nearly 2 cm. long. 

In sandy swamps, in the coastal plain, North Carolina to Florida. Black Pine. Pond Pine. 

6. Pinus glabra Walt. A tree reaching a height of 40 m., with a maximum trunk 
diameter of 1.2 m., the trunk and branches clothed with a relatively smooth and close 
bark, and bearing spreading branches near the ground, except in the case of very old trees. 
Leaves glaucous, 2 in a sheath, very slender, 4-8 cm. long, numerous or somewhat crowded : 
sheaths 5-8 mm. long: staminate aments fully 1 cm. long: cones 3.5-5 cm. long, conic 
when closed, ovoid when open, the appendages bearing minute or almost obsolete spines, 
and often essentially unarmed : seeds about 4 mm. long, the wing usually 1.5 cm. long. 

In river swamps or hammocks, South Carolina to Florida and Louisiana. Spruce Pine. Cedak 
Pine. White Pine. Walter's Pine. 

7- Pinus echin^ta Mill. A tree reaching a height of 40 m., with a maximum trunk 
diameter of 1.35 m., the trunk clothed with a coarsely furrowed and very rough bark, with- 
out branches on the lower part, except in the case of young trees. Leaves deep green, 2 
in a sheath or sometimes three together, 8-12 cm. long, slender : sheaths 10-15 mm. long : 
staminate aments 1-1.5 cm. long; cones 5-6.5 cm. long, conic when closed, ovoid when 
open, each appendage armed with a slender spine : seeds 4-5 mm. long, the wing 1.5-2 
cm. long. [P. mi7is Michx.] 

In sand or clay or on rocky banks, New York to Kansas, Florida and Texas. Short- leaved Pine. 
Yellow-Pine. 

8. Pinus clausa Chapra. A tree reaching a height of 24 m., with a maximum trunk 
diameter of 7.5 dm., the bark relatively smooth. Leaves deep green, 2 in a sheath, 4-8 
cm. long, very slender, rather crowded : sheaths 5-7 mm. long : cones 4.5-6 cm. long, conic 
when closed, ovoid when open, the appendages of the scales each armed with a stout spine 
at the middle or behind it : seeds 4 mm. long, the wings about 1.5 cm. long. 

In sandy ridges near the coast, Florida and Alabama, Sand Pine. 

9. Pinus Virginlina Mill. A tree reaching a height of 36 m., with a trunk diameter 
of 1 m., but often much smaller, the bark more or less flaky, the twigs glaucous. Leaves 
deep green, 2 in a sheath, 4-7 cm. long, rather stout : sheaths 5-8 mm. long : staminate 
aments 1-1.5 cm. long: cones 5-7 cm. long, narrowly conic when closed, ovoid when 
open, the appendages of the scales each armed with a curved spine : seeds 4-5 mm. long, 
the wing fully 1.5 cm. long. [P. inop^ Ait.] 

In sandy soil or on stony ridges, Long Island to Indiana, Georgia and Alabama. Scrub or Jersey 
Pine. Poverty Pine. 

10. Pinus rigida Mill. A tree reaching a height of 25 m., with a maximum trunk 
diameter of 9 dm., the bark very rough, the twigs yellow. Leaves bright green, 3 in a 
sheath, 6-12 cm. long, rather stout : sheaths 10-15 mm. long: staminate aments about 1.5 
cm. long : cones 4-7 cm. long, ovoid when closed, globose-ovoid or depressed when open, 
the appendages of the scales relatively thin, each armed with a more or less recurved spine. 

In sandy or rocky soil, New Brunswick to the Lake Ontario region, Virginia and Kentucky and in 
the mountains to Georgia and Alabama. Pitch Pine. 



A 

« 



PIXACEAE 



29 



11. Pinus piingens Michx. A tree reaching a heiglit of 18 m., with a mnxinnirn 
trunk diameter of about 1 m., the bark rather smooth but flaky. Leaves light green, 2 in 
a sheath, 5-10 cm. long, stout, rigid : sheaths 12-14 mm. long: staminate aments 1-1.5 
cm. long : cones 8-12 cm. long, ovoid when closed, globose-ovoid or depressed when open, 
very persistent, the appendages of the scales very thick, each armed with a stout incurved 
spine : seeds 6-7 mm. long, the wing fully 2 cm. long. 

In stony soil or on cliffs, Allegheny Mountains and the Blue RirJjje from Pennsylvania to northern 
Georgia, and locally in the contiguous territory. Table Mountain Pine. 

2. CARYOPITYS Small. 

Monoecious evergreen shrubs or trees. Leaves needle-like, 2-3 together, or solitary, 
each with 1 fibro-vascular bundle, each cluster surrounded at the base by a deciduous sheath. 
Staminate aments clustered at the ends of branchlets of the preceding year. Anthers 2- 
celled, each sac opening lengthwise. Pollen-grains with two lateral empty cells. Pistil- 
late aments borne behind the terminal bud. Cones maturing the second year : scales be- 
coming leathery, with the dorsal thickenings often minutely spine-tipped. Seed-wing very 
narrow or a mere margin which remains attached to the scale when the seed falls. 

1. Caryopitys ^dulis (Engelm.) Small, A tree often becon)ing 12 m. tall, with 
irregularly ridged bark. Leaves 2 or rarely 3 in a sheath, 2-5 cm. long, rigid, dark green : 
sheaths 6-12 mm. long, early deciduous : staminate aments 6-9 ram. long: pistillate aments 
oblong-cylindric, short-peduncled : cones ovoid, 4-6 cm. long ; scales much thickened back 
of the apex, each enlargement with a minute incurved tip : seeds ovoid, fully 1 cm. long, 
the wing about 3 mm. wide, detached from the seeds at maturity. {^Pinns edulis Engelm.] 

On limestone bluffs or in arid soil. Wyoming to Texas and Mexico. Spring. Nut Pine. PiSon. 

ft 

3. STROBUS Opiz. 

Monoecious evergreen trees. Leaves needle-like, mostly with 1 fibro-vascular bundle, 
5 together, surrounded at the base by a deciduous sheath, the clusters spreading in all direc- 
tions. Staminate aments in spikes or clusters at the ends of brachlets of the preceding 
year. Anthers 2-celled, opening longitudinally. Pollen-grains of 3 cells ; 2 lateral cells 
empty. Pistillate aments slightly elongated, on twigs behind the terminal bud : scales 
crowded in several series. Cones maturing the second year, drooping : scales becoming 
leathery, without either dorsal thickening or spine. Seeds winged. 

1. Strobus Strobus (L.) Small. .A forest tree of the first economic importance, 
reaching a height of 52 m., with approximately whorled branches, bark relatively smooth, 
often shining. Leaves very slender, 5 in a sheath, often rather crowded, 5-10 cm. long, 
glaucous, nearly triangular in cross-section : sheaths deciduous or fugaceous : staminate 



aments ovoid or oblong, 8-10 mm. long, glaucous, in dense clusters : pistillate aments nar- 
rowly oblong, about 1 cm. in length, glaucous : cones narrowly cylindric, 1-2 dm. long, 
somewhat tapering towards the apex, more or less curved ; scales at length loosely spreading, 
thinnish : seeds elliptic, 6-7 mm. long; wing usually about 2.5 cm. long. [Pinus Strobus Lt,^ 

In woods, Newfoundland to Manitoba, south to New Jersey and Iowa, and in the mountains to 
northern Georgia and Alabama. Spring. White Pine. 

4. PICEA Link. 

Evergreen monoecious trees, with soft wood. Leaves ascending or nearly erect : blades 
needle-shaped, but short, nearly terete or 4-angled, curved, leaving a prominent base on 
falling away. Staminate aments arising from the axils of the leaves of the preceding year, 
or sometimes terminal. Pollen-sacs loosely disposed, opening longitudinally. Pistillate 
aments terminal : scales closely imbricated : bracts membranous, inconspicuous. Cones 
maturing the first year, drooping ; scales thinnish, persistent, at length spreading. Seeds 
samara-like, each with a hyaline wing. The plants flower in spring. 

Twigs stout, copiously pubescent : leaves over 1 mm. broad, blunt or mucronate : cones persistent. 

' 1. P. Mariana. 

Twigs slender, glabrate or merely pubescent between the decurrent sterigmata : leaves 

barely 1 mm. broad, acute : cones early deciduous. 2. P. aiisfralis, 

1. Picea Mariana (Mill. ) B.S.P. A forest tree reaching a height of 30 m., with a 
maximum trunt diameter of about 1 m. Bark slightly roughened : twigs stout, stiff, copi- 
ously pubescent as are usually the sterigmata: leaves stout, curved, 8-12 mm. long, over 1 
mm. thick, blunt or mucronate, deep green : cones oval or ovoid, 2.5-4 cm. long, persistent. 

In moist soil, Newfoundland to the Northwest Territory, New Jersey and Minnesota, and in the 
mountains to North Carolina. Black Spruce. He Balsam. Tamarack. Yew Pine. Lashhorn. 



30 JUNIPERACEAE 

2, Picea austr^lis Small. A forest tree sometimes 35 or 40 m. tall, with a maximum 
trunk diameter of nearly 1.5 m. Bark relatively smooth : twigs slender, glahrous or merely 
pubescent in lines between the deeurrent sterigmata : sterigmata glabrous : leaves slender, 
straight or slightly incurved, 8-14 mm. long, barely 1 mm. thick, acute, bright green: 
cones oblong, oval or ovoid, rarely 2.5 cm. long, deciduous. [P. alba Chapm., not Link.] 

On dry mountain slopes or summits, or about ledges of rock, Virginia and North Carolina. 

5. TSUGA Carr. 

Stately monoecious evergreen trees, with spreading or somewhat declining branches 
and a brittle wood. Leaves apparently 2-ranked : blades flat, linear, glaucous beneath, 
articulated at the base of the petiole. Staminate aments on slender stalks arising from the 
axils of the leaves of the preceding year. Pollen-sacs subglobose, confluent, opening trans- 
versely. Pollen-grains 2-lobed or discoid. Pistillate aments solitary and terminal on the 
branchlets of the preceding year : scales in few series : bracts membranous, inconspicuous. 
Cones elongated, drooping, maturing the first year : scales at length loose or spreading, 
persistent Seeds samara-like, each with a delicately striate wing. 

Twigs tomentose with long hairs : cones narrowly ovoid, 1.8-2.3 cm. long : scales nearly erect. 

1. T, Canadeiis^is. 

Twigs 4«mentose with short hairs, or glabrate : cones cylindric-oblong, 3 cm. long: 

scales spreading at right angles. 2. T. CaroUniana, 

1. Tsuga Canadensis (L.) Carr. A forest tree reaching a height of 31 m., with a 
maximum trunk diameter of 1.2 m., clothed with a thin bark which exfoliates in scales. 
Branches lax, somewhat declining : leaves 6-14 mm. long; blades linear, obtuse, slightly 
revolute, glabrous, shining, with a furrow along the midrib above, glaucous beneath : twigs 
reddish, tomentose with long hairs : staminate aments subglobose, 2 mm. in diameter: cones 
narrowly ovoid, 1.8-2.3 cm. long; scales suborbicular, thinnish, nearly erect, the tips 
slightly revolute : seeds oblong, 4 mm. long, oblique at the ends ; wings 1 cm. long or shorter. 

On rocky banks, in woods and ravines, Nova Scotia to Quebec and AVisconsin, south to Delaware, 
and on the Alleghenies or in their vicinity to northern Georgia and Alabama. Spring. Hemlock. 
Spruce Pine. 

2. Tauga Carolini^na Engelm, A tree rarely reaching a height of 25 m. and a 
maximum trunk diameter of 1 m., the bark rather smooth. Branches bristly, spreading 
horizontally : leaves 1.2-2 cm, long ; blades linear, obtuse or notched at the apex, glabrous 
and shining above, glaucous beneath, somewhat revolute : twigs tomentose with short hairs 
or glabrate : staminate aments ovoid, 3 mm. long : cones cylindric-ovoid, 3 cm. long ; 
scales oblong or nearly so, thinnish, at length spreading at right angles, the tips slightly 
involute : seeds ovoid, 4 mm. long, covered with resinous glands ; wings 1.2-1.5 cm. long. 

In ravines and on rocky mountain slopes from southwestern Virginia to northeastern Georgia. 
Spring. Hemlock. Crag Hemlock. Carolina Hemlock, 

^ 

6. ABIES Mill. 

Small or medium sized monoecious evergreen trees, with spreading or somewhat droop- 
ing branches and soft but compact wood. Leaves sometimes apparently 2-ranked, narrow, 
flattish or strongly keeled and glaucous beneath, leaving no prominent points of attach- 
ment in falling away. Staminate aments arising from the axils of the leaves of the preced- 
ing year, solitary, subtended by imbricated bracts. Pollen-sacs loosely disposed, opening 
transversely or nearly so. Pistillate aments lateral, elongated, erect : scales densely im- 
bricated ; bracts membranous, conspicuous, deciduous at maturity. Cones maturing the 
first year, cylindric, erect : scales spreading at right angles. Seeds samara-like. 

1. Abies Fr^seri (Pursh) Lindl. A tree reaching a height of 25 m., with balsam- 
yielding blisters on the trunk. Leaves curved ; blades linear, 1-2 cm. long, flattish, rather 
thick, slightly keeled beneath, obtuse or notched at the apex, smooth and shining above, 
glaucous beneath, sessile : twigs pubescent ; staminate aments 5-8 mm. long, nearly sessile : 
cones cylindric, 4-5 cm, long, rounded at each end, their scales fan-shaped, compactly 
arranged ; bracts suborbicular, surpassing the scales, reflexed, erose and apiculate : seeds 
4-5 mm. long, each w^ith a short wing which is nearly as broad as long. 

On mountain peaks, southern Virginia to Tennessee and North Crolina. Spring. Fir. Silver 
Fir. She Balsam. Lash Horn. 

Family 2. JUNIPERACEAE Horan. Juniper Family. 

Usually evergreen dioecious or monoecious trees or shrubs, commonly conic 
in outline. Buds naked. Leaves opposite or whorled, mostly reduced to ap- 



JUNIPERACEAE 



31 



1. Taxodium. 



pressed scales, or sometimes subulate and spreading. Periantli wanting. 
Staminate aments solitary, variously disposed. Pistillate aments mostly soli- 
tary, of few carpellary scales. Ovules naked, erect, 1 or several at the base of 
each carpellary scale. Fruit a cone of often peltate scales, or sometimes fleshy 
and berry-like or drupaceous. Seeds wingless, or winged, the wing a portion of 
the testa. Cotyledons 2 or more. 

Plants monoecious : cones dry : scales merely imbricated. 
Leaves not scale-like, spreading. 
Leaves mostly scale-like, typically appressed|and imbricated. 

Cones elongated : scales not peltate: seeds winged at both ends. 2. Thuja. 

Cones nearly globose : scales peltate : seeds slightly winged. 3. Chamaecyparis. 

Plants mostly dioecious : cones berry-like or drupe-like ; scales fleshy, coalescent. 
Leaves subulate and spreading on the mature branches : aments axillary, the 

pistillate with smaller scales at the top. 4. Juniperus. 

Leaves scale-like and appressed on the mature branches: aments terminal, 

the pistillate.with larger scales at the top. 5. Sabina. 

1. TAXODIUM L. C. Eich.^ 

Deciduous-leaved monoecious trees, with lax branches. Bark thin, smooth, fibrous. 
Leaves narrow, often almost 2-ranked, normally spreading. Staminate aments in panicled 
spikes or racemes. Anthers stalked on an oblong column, 2-5-celled, crowded, opening 
longitudinally. Pistillate aments subglobose, sessile on the branchlets of the preceding 
year, solitary or in pairs : scales peltate, crowded. Ovules erect, 2 on each scale. Cones 
globose or obovoid, closed, their scales orbicular or oblong, shield-like, each base narrowed 
into a stalk. Seeds angled, not winged. Testa shining. Embryo with 6-9 cotyledons. 

Leaves 2-ranked, widely spreading : branchlets horizontal : bark thin, comparatively smooth. 

1. T. dUtichum, 
Leaves appressed to the appressed branchlets : bark thick, strongly furrowed. 2. T. imbricarium , 

r 

1. Taxodium distichum (L. ) L. C. Eich. A tree sometimes 49 m. tall and rarely 
4 m. in diameter above the enlarged base, with soft light, but compact and durable w^ooa. 
Roots producing hollow conic knees sometimes 2 m. tall : base of the trunk conic, usually 
hollow, with very prominent narrow^ longitudinal ridges: bark thin, comparatively smooth : 
branchlets narrowly horizontal : leaves spreading, 2-ranked ; blades linear, often falcate, 
1-1.5 cm. long, acute, sessile : staminate aments 1-2 mm, in diameter, in naked drooping 
panicled spikes : pistillate aments in the axils of the leaves, with crested scales : cones 
globular, 2.5 cm. in diameter : seeds 8-10 mm. long. 

In swamps, in or near the coastal plain, usually along the larger rivers and over calcareous rocks, 
Delaware to Florida and Texas, ascending the Mississippi Valley to Missouri and Indiana. Spring.— A 
Mexican species, T, mucrandtum Tenore, may occur in southern Texas. Cypress. Bald Cypress. 

2. Taxodium imbric^rium (Nutt.) Harper. A tree usually smaller than T. disit- 
churriy sometimes attaining a height of 25 m. and a diameter of 1 m. above the enlarged 
base, the w^ood usually heavier and stronger than that of the preceding species, the knees 
less abundant and short and rounded. Base of the trunk conoidal, hollow, often 3 or 4 
times the diameter of the trunk proper, with broad rounded or almost obsolete longitudinal 
ridges : bark thick, coarse and furrowed : branchlets normally erect : leaves appressed to 
the branchlets (but on shoots often resembling those of T. distichum)^ incurved : blades subu- 
late, 0.5-1 cm. long, sessile : inflorescence and fruit very similar to that of T. distichum. 

In lakes, pine-land ponds, creeks and small rivers in the coastal plain, apparently always over a 
clay subsoil, Virginia (Dismal Swamp) to Florida and Alabama. Spring. PoNi) Cypress. 

2. THUJA L. 

Evergreen monoecious shrubs or trees narrowly conic in outline. Branchlets 2-ranked. 
Leaves scale-like, opposite, 4-ranked, flat or concave, often with a glnnd on the back, be- 
coming longer and less densely imbricated on the older parts. Staminate aments terminal, 
solitary, nearly sessile between the leaves. Anthers in 2 or 3 series, 4-celled, stalked. 
Pistillate aments solitary, terminal, on short twigs, ovoid or oblong : scales opposite, in 
several series. Ovules 2 or rarely 3-5, erect at the base of each scale. Cones ovoid or ob- 
long, drooping, persistent : scales dry, spreading. Seeds flat, broadly winged on both sides. 

1- Thuja occident^lis L. A shrub or small tree reaching a height of 18 m., rarely 
with a trunk diameter of 1.5 m., producing light and soft but durable wood. Branches 
zigzag : leaves scale-like, appressed, each bearing a gland on the back, those of the branches 

— I 

^ Contributed by Mr. Roland M, Harper. 



32 



JUNIPERACEAE 



5-7 mm. long, sliarp-pointed, those of the twigs of two forms, one set opposite, flat, acute, 
the other boat-shaped, overlapping the edges of the flat ones : staminate aments in depres- 
sions, 1.5-2 mm. in diameter: cones oblong, 1-1.3 cm. long, brown, drooping ; scales ovate 
or oblong, obtuse, with a gland at the apex, at length loose and spreading : seeds elliptic, 5 
mm. long, narrowed at each end ; Aving 6-7 mm. long, notched at each end. 

In swamps and on rockv banks, New Brunswick to Lake AVinnipeg, south to Pennsylvania and in 
the Alleghenies to North Carolina and Tennessee. Spring. Arbor Vitae. M hue Cedar. 

3. CHAMAECYPARIS Spach. 

Evergreen monoecious strong-scented trees, with 2- ranked branchlets. Leaves imbri- 
cated, scale-like, or sometimes subulate on twigs, opposite, 4-ranked, each wuth a gland 
on the back. Staminate aments terminal, sessile or nearly so. Anthers 2-4-celled, in the 
side of a shield-like scale. Pistillate aments terminal, globose, of several series of opposite 
scales. Ovules erect, 1-4 at the constricted base of each scale, bottle-shaped. Cones glo- 
bose, woody : scales more or less angled, thick, with points or knobs on the back. Seeds 
angled or slightly winged. 

1. Chamaecyparis thyoides (L.) B.S.P. A small or medium-sized strong-scented 
tree, reaching a height of 27 m. and a maximum trunk diameter of 1.2 m,, producing soft 
light but compact and durable wood. Leaves scale-like, 1-2 mm. long, 4-ranked, imbri- 
cated, covering the branchlets, acute, the lateral keeled, the vertical merely convex ; those of 
twigs subulate: staminate aments 2-3 mm. long, slightly^ broadened upward: pistillate 
aments about 2 mm. in diameter, glaucous, their scales with hyaline appendages : cones 
globose, somewhat angled, 5-7 mm. in diameter ; scales at length widely spreading, pointed 
on the back : seeds narrowly winged. [_Chamaecyparis sphaeroidea Spach. J 

In swamps and sandy places, mostly near the coast, southern Maine to Florida and Mississippi. 
Spring. White Cedar. Cypress. 

+ 

4. JUNfpERUS L. 

Evergreen dioecious or monoecious shrubs or trees, with decumbent or erect stems. 
Leaves in whorls of 3, subulate, neither appressed nor imbricated, without glands on the 
back, jointed at the base. Staminate aments axillary, solitary. Pollen-sacs several under 
each scale. Pistillate aments of 2-3 rows of fleshy scales. Ovules usually solitary, erect. 
Cone berry-like by the accrescent scales of the pistillate aments. Seeds 1 or several, enclosed 
in the cones, wingless. * ^ 

A depressed shrub, with creeping branches : leaves abruptly bent at the base, deeply channeled, rather 
abruptly pointed. 1. J. Sibirica. 

A tree or an erect shrub : leaves straight or nearly so, shallowly channeled, gradually acuminate. ^ 

2, J, communis. 

1- Junipems Sibirica Bnrgsd. A depressed radially spreading shrub, with creeping 
branches, forming extensive patches, seldom rising over 5 dm. above the ground. Leaves 
stout, mostly 8-12 mm. long, abruptly curved at the base, appressed or erect-ascending, 
densely crowded, abruptly pointed : cones subglobose, 8-10 mm. in diameter. 

In dry or stony soil, Labrador to Alaska and in the Appalachian Mountains to North Carolina and 
Tennessee, and in the Rocky Mountains to Colorado and Utah. Also in Europe and Asia. Spring. 

2. JnnipeniB communis L. An erect shrub or a narrowly conic tree, attaining a 
height of 8 m. and a maximum trunk diameter of 0.5 m. Leaves 1-2 cm. long ; blades 
narrowly linear, sometimes gradually narrowed upward into a very sharp point, somewhat 
concave and glaucous above, keeled beneath, sessile, usually spreading: staminate amenis 
oblong, 4-5 mm. long, sessile: pistillate aments narrowly ovoid, glaucous: cones globose, 
6-8 mm. in diameter, dark blue, covered with a bloom : seeds ovoid, about 3 mm. long, 
more or less flattened, 3-angled below the apex, roughened. 

On dry rocky hills, Labrador to the Rocky Mountains, southward to Georgia and New Mexico. 
Also in Europe and Asia. Spring. Juniper. 



5. SABINA Haller. 



Evergreen strong-scented monoecious or dioecious shrubs or trees. Leaves mostly 
scale-like, each with a gland on the back, appressed and imbricated at maturity, opposite, 
sometimes connate at the base, or sometimes subulate on the twigs. Staminate aments very 
small, solitary or 3-6 together, terminal on the branchlets. Pollen-sacs 3-6 under each 
ovate or shield-like scale. Pistillate aments subglobose, composed of 2-3 rows of fleshy 



TAXACEAE 



33 



scales. Ovules erect, 1 or sometimes 2 under each scale. Cone berry-like by the acrescent 
fleshy scales, which enclose the seeds. Seed 1-4, wingless. 

Cones 3-6 mm. long : seeds 2-4 mm. long, smooth. 

Staminate aments 4-5 mm. long: cones 5-6 mm. long. ], S. Virginlana, 

Staminate aments 3-4 mm. long : cones 3-4 mm. long. 2. S. Barbademk, 

Cones 8-10 mm. long : seeds G-8 mm. long, ribbed. 3, S, mhinoides, 

1. Sabina Vlrglnlina ( L. ) ^ Antoine. A shrub-like or conic tree, reaching a height 
of 30 m. and a maximum trunk diameter of 1.5 m., clothed with a shreddy bark, and with 
a durable red heart-wood. Leaves often of 2 forms, those on the twigs awl-shaped, spread- 
ing, about 1 cm. long, but normally scale-like, appressed, acute, opposite and 4-ranked, or 
in whorls of 3, 1-4 mm. long, Avith a gland on the back : staminate aments oblong, 3-4 mm. 
long, numerous : cones ovoid, 5-6 mm. in diameter, blue, covered with a bloom : seeds 
ovoid, flattened, 3-4 mm. long, smooth, shining. \_Juniperu8 Virginiana L.J 

On dry hills and in swamps throughout the United States and southern British America. Spring. 
Fruit ripe in fall. Red Cedar, Savin. 

2. Sabina Barbad^nsis (L. ) Small. A shrub or tree similar in habit to S. Virginiana^ 
but with shorter and rather thicker leaves, the relatively blunt apex closely appressed. 
Staminate aments 4-5 mm. long : berry-like cones ovoid or oval-ovoid, 3-4 mm. long. 
\_Juniperu8 Barhadensis L. ] 

In sandy or clay soil, Florida to Texas, along or near the coast. Spring. Also in the West Indies. 

3. Sabina sabinoidea (H.B.K. ) Small. A shrub or small tree, reaching a height 
of 15 m. and a maximum trunk diameter of 3 dm., clothed with a shreddy bark and pos- 
sessing a brown wood. Leaves scale-like, appressed, imbricated, 1-2 mm. long, opposite, 
or four-ranked, obtuse, minutely fringed : staminate aments oblong, about 4 mm. long : 

Eistillate aments 2-3 mm. long, with very large spreading terminal scales : cones subglo- 
ose, 8-10 mm. in diameter, covered with a bloom : seeds ovoid, 6-8 mm. long, flattened, 
1-4 in a cone, ribbed. [Juniperns sabinoides (H.B.K. ) Sargent.] 

On hillsides, mostly in limestone soil, Texas and Mexico. Winter and spring. Mountain Cedar. 

Family 3. TAXACEAE Lindl. Yew Family. 

Evergreen monoecious or dioecious shrubs or trees, mostly destitute of resin, 
with scaly buds. Leaves spirally disposed but usually spreading as if 2-ranked : 
blades simple, entire, rigid. Aments axillary or terminal ; staminate small, 
naked or subtended by imbricated bracts. Pollen-sacs under variously shaped 
scales, opening longitudinally. Pistillate flowers solitary, or one only maturing, 
consisting of an orthotropous ovule ; this sessile, without a carpellary scale. 
Fruit berry-like, erect, nearly enclosed in the accrescent pulpy aril, or naked. 
Testa bony or woody. Endosperm fleshy or mealy, sometimes channeled. 
Cotyledons 2. 

Pistillate flowers 2 together : pollen-sacs 2 : fruit naked: endosperm channeled. 1. Tr: 

Pistillate flowers solitary : pollen-sacs 6-8: fruit surrounded by an aril : 



endosperm even. 2. Taxus. 



1. TUMION Kaf. 



Medium-sized dioecious conic evergreen trees, with a light but hard and compact 
wood. Branches whorled : branchlets 2-ranked. Leaves spreading as if 2-ranked : blades 
linear, flat. Staminate aments often crowded, each arising from a set of imbricated bracts, 
sessile in the axils of the leaves. Pollen-sacs 2 under each scale. Pistillate aments soli- 
tary, erect, consisting of 2 ovules, these sessile in a set of persistent bracts. Seeds berry- 
like, elongated, with a fleshy pericarp. \_Torreya Arn., not Raf.] 

1. Timuon taxifolium (Arn.) Greene. Alow or medium-sized tree, reaching; a 
height of 18 m., with a maximum trunk diameter of 0.9 m,, when bruised exhaling a dis- 
agreeable odor. Twigs puberulent : leaf-blades linear, 1.5-3 cm. long, slightly narrowed 
upward, tipped by a hard sharp point, somewhat revolute, longitudinally wrinkled beneath, 
short-petioled : staminate aments subglobose, 5-7 mm. in diameter, yellow, often crowded, 
subtended by broadly ovate keeled scales : seed globose-oblong or somewhat obovoid, 3-4 
cm. long, smooth, glaucous. [Torreya taxifolia Arn.] 

Along the Apalachicola River, western Florida. Rare and local. Spring. Stinking Cedar. 

2. TAXUS L. 

Low often diffuse dioecious or rarely monoecious evergreen trees, or shrubs. Leaves 
spreading as if 2-ranked : blades flat, usually pointed, often scythe-shaped. Staminate 

3 



34 



TYPHACEAE 



aments short-stalked, subtended by involucres of several imbricated bracts arising from the 
axils of the leaves. Pollen-sacs 6-8 under each shield-like scale. Pistillate aments erect, 
consisting of usually one ovule ; this sessile in an involucre of several imbricated bracts. 
Aril accrescent into a pulpy cup. Seed nut-like, elongated, exposed only at the apex. 

1. Taxus Floridkna Nutt. A low tree ranging from 3-6 m. in height, with a maxi- 
mum trunk diameter of 0.25 m., producing a heavy, hard and compact wood. Branches 
horizontally spreading ; branchlets 2-ranked : leaves 1-2 cm. long ; blades narrowly linear, 
sharply apiculate, revolute, sometimes glaucescent beneath, narroM'ed into short twisted 

f»etioles ; midrib prominent on both surfaces : fruit berry-like ; aril bright red, 6-10 inm. 
ong : seed ovoid, 5-7 ram. long, minutely wrinkled, narrowed into a short tip. 

Oil river banks, western Florida. Rare and local. Spring. Yew. 

Class 2. ANGIOSPERMAE. 

Carpel or pistil a closed cavity formed by the uniting of the margins of 
a rudimentary leaf, or sometimes of several leaves. The ovules (macro- 
sporanges) are borne on the inner face of this cavit}^ and within it the 
seeds are matured. A pollen-grain alighting on the stigma (a specialized 
portion of the carpel) sends out a pollen-tube which penetrates the tissues 

r 

of the carpel and on reaching an ovule enters its orifice (raicropyle); or 
rarely the pollen-tube enters at the chalaza. Fertilization is effected by 
a sperm-cell at the end of a pollen-tube coming in contact with an egg cell 
in the embryo-sac. 

Cotyledon 1: stem endogenous. Subclass 1. Monocutyledoxes. 

■Cotyledons norinally 2 : stem exogenous (with rare exceptions). Subclass 2. Dicotyledones. 

Subclass 1. MONOCOTYLEDONES. 

Stems endogenous, with no distinction into bark, wood and pith, con- 
sisting of a ground-mass of soft tissue (parenchyma) in which strands or 
bundles of wood cells are irregularly distributed. Leaves mostly alter- 
nate, sheathing at the base : blades usually parallel-nerved, entire or essen- 
tially so, rarely separating by a manifest articulation. Perianth and essen- 
tial parts of the flower usually in threes or sixes. Embryo with a single 
cotyledon, the early leaves always alternate. 

Order 1. PANDANALES. 

Aquatic, or marsh-inhabiting herbs, perennial, mostly with elongated root- 
stocks. Leaves alternate, with narrow elongated blades. Flowers incomplete 
and imperfect, in elongated or head-like spikes. Perianth of bristles or scales. 
Androecium of 2-7 stamens. Gynoecium a single carpel, or rarely of 2 united 
carpels. Ovary 1-2-celled. Fruit nut-like. Endosperm mealy or fleshy. 

Flowers in elongated terminal spikes: fruit hidden among bristles. ' Fam. 1. Typhaceae. 

Flowers in globose axillary spikes : fruit not hidden among bristles. Fam. 2. Sfargamaceak. 

Family 1. TYPHACEAE J. St. Hil. Cat-tail Family. 

Perennial marsh herbs, with long rootstocks and glabrous foliage. Stems 
simple^ terete. Leaves sheathing at the base : blades linear, sword-like, flat. 
Flowers monoecious, in dense spikes, these subtended by fugacious bracts; 
staminate spike above the pistillate. Perianth of several bristles. Stamens 2- 
7. Filaments united at the base. Anthers oblong or broadened upward. Ovary 
1-2-celled, stalked. Stigmas club-shaped^ oblong or rhomboidal. Ovules sus- 
pended, anatropous. Accompanying the stamens and pistils are numerous 
bristles, while among the pistillate flowers are other sterile flowers in the form 
of club-shaped hairs. Fruit nut-like. Endosperm copious. 



SPARGANIACEAE 



35 



1. TYPHA L. 

Characters of the family. Cat-tail. Eeed Mace. 

Spikes with pistillate and staminate portions separated ; pistillate with bractlets ; stigmas linear : pol- 
len of simple grains. 

Hairs accompanying the pistillate flowers not thickened at the apex. 1. T. angustifolia. 
Hairs accompanying the pistillate flowers with club-shaped tips. 2. T. Domingaiais. 
Spikes with pistillate and staminate portions contiguous : pistillate without bract- 
lets : stigmas club-shaped or rhomboidal : pollen grains in 4's. 3. T. latiJoUa. 

1. Typha angustifolia L. Stems 1.5-3 m. tall, slender, not jointed: leaf-blades 
narrowly linear, 5-15 mm. wide, finely striate-ridged : spikes light brown, 1-4 dm. long ; 
pistillate portion with bractlets, 0.5-1.5 cm. thick ; staminate part separated from the pis- 
tillate : stigmas linear or oblong-linear : pollen-grains simple : nutlets terete, not bursting 
in water : outer coat of seeds not separable from the inner. 

In marshes, chiefly along the coast, Nova Scotia to Florida. Summer. Also in Europe and Asia. 

■ 

2. Typha Doming^nsis Pers. Similar to T. angustifolia^ but larger. Leaf-blades flat 
or nearly so, the lower ones often 2 cm. broad : spikes 4-6 dm, long, the pistillate portion 
10-20 mm. thick : hairs accompanying the pistillate flowers, or most of them, with mani- 
fest club-shaped tips. 

In marshes or low grounds, Florida, Texas and California. Also in tropical America. Summer 
and fall. 

3. Typha latifolia L. Stems 1-2.5 m. tall, stout, not jointed: leaf -blades linear, 
10-25 mm. wide, contracting much in drying: spikes dark brown or black, 1.5-6 dm. 
long; pistillate portion destitute of bractlets, 2.5-3 cm. thick ; staminate part contiguous 
with the pistillate : stigmas spatulate or rhomboidal: pollen-grains in 4's: nutlets fur- 
rowed, bursting in water : outer coat of the seeds separating from inner. 



In marshes nearly throughout North America. Summer and fall. Also in Asia and Europe. 



Family 2. SPARGANIACEAE Agardh. Bur-reed Family. 

Perennial marsh or aquatic herbs, with horizontal rootstocks. Stems erect 
or floating. Leaves alternate : blades sheathing at the base, narrow. Flowers 
monoecious, in dense heads on the upper part of the stem and its branches. 
Heads globose, sessile or peduncled ; staminate uppermost. Spathes bract-like, 
sometimes remote from the head or its peduncle. Perianth of several (3-6) 
scales. Stamens mostly 5. Filaments distinct. Anthers oblong, or cuneate. 
Ovary 1-2-celled. Stigmas slender. Ovules anatropous. Fruit nut-like. 
Endosperm copious, surrounding the straight embryo. 



1, SPARGANIUM L. 

Characters of the family. Bur-reed. The plants flower in spring and summer. 



1. 5. androdadam, 

2. S, Amencanum, 

3. S, eurycarpum. 



Nutlets stalked, fusiform. 

Upper leaves with neither sac-like bases nor hyaline margins : achenes abruptly 

narrowed into the slender style. 
Upper leaves with sac-like bases and hyaline margins : achenes gradually nar- 
rowed into the conspicuous styles. 
Nutlets sessile, obovoid or cuneate, 

1. Sparganium androcladum (Engelm.) Morong. Foliage glabrous or nearly so. 
Stems 2-7 dm. tall, more or less branchea : leaf-blades linear, attenuate, sometimes quite 
numerous : staminate heads usually less than 1 cm. thick : pistillate heads 3-7, sessile or 
peduncled : bractlets broadest at the eroded apex, as long as tne nutlets or shorter : fruiting 
heads globose, 1-2 cm. in diameter : nutlets fusiform, more or less constricted at the middle, 
4-6 mm. long, each abruptly narrowed into a slender style. [*S. simplex Chapm,, not Huds.] 

In swamps or shallow water, Nova Scotia to British Columbia, Florida and Louisiana. 

2. Sparganium Americ^num Nutt. Similar to S. androcladum,^ but the stem simple, 
the lower heads of the inflorescence merely peduncled. Leaves drying green, the upper 
with more or less sac-like bases and broad hyaline-scarious margins : nutlets slightly angled, 
each gradually narrowed into a stout conspicuous style. 

In low grounds or ponds. Ontario to British Columbia, Pennsylvania, and the Indian Territory. 

3. Sparganium eurycArpum Engelm. Foliage glabrous. Stems 8-20 dm. tall, 
branched : leaf-blades linear, attenuate, flat or slightly keeled beneath, the lower ones 9-15 
dm. long, the upper shorter : staminate heads about 1 cm. thick : pistillate heads several, 



I 



36 ZANNICHELLIACEAE 



sessile orpednncled, accrescent : "bractlets broadened upward, as many as the angles of the 
nutlets, entire or eroded at the apex : fruiting heads globose, 2-2.5 cm. in diameter : nutlets 
6-10 mm. long, sessile, 4-5-angled, rounded or depressed at the apex, tipped with the style. 

Along streams or in marshes, Newfoundland to British Columbia, North Carolina and California. 



Order 2. NAIADALES. 

Aquatic or marsh-inhabiting herbs, perennial by rootstoeks. Leaves various, 
sometimes reduced to phyllodes, sometimes with both narrow and broad blades 
on the same plant. Flowers perfect, monoecious or dioecious, usually with an 
unequal number of parts in the whorls. Perianth wanting or very imperfect. 
Androecium of 1-4 stamens or sometimes more. Gynoecium of 1 or several 
distinct or united carpels. Endosperm scant or wanting, 

Gynoecium of distinct carpels : stipmas disk-like or cup-like. Fam, 1. Zannichelliaceak. 

Gynoecium of united carpels: stigmas 2-4. slender. 

Staminate and pistillate flowers alternating on a slender spadix, later- 
ally attached : leaves with entire blades. Fam. 2. Zosteraceae, 
Staminate and pistillate flowers axillary, attached at the base : leaves 

with spiny-toothed blades. Fam. 3. Naiadaceae. 

Family 1. ZANNICHELLIACEAE Dumort. Pondweed Family. 

Perennial submersed caulescent herbs. Leaves alternate, sometimes clus- 
tered : blades filiform or expanded. Flowers perfect or monoecious, in axillary 
sometimes peduncled spikes or clusters arising from a spathe. Perianth a hya- 
line envelope, or wanting, Androecium of 1-4 stamens or rarely more. Fila- 
ments distinct, hypogynous in the perfect flowers. Anthers 1-2-celled, extrorse. 
Gynoecium of several distinct carpels. Ovaries 1-celled. Ovule solitary. Fruit 
a spike or cluster of drupelets. Endosperm wanting. 

stamens 2 or sometimes solitary, the connectives without appendages : drupelets manifestly stipitate. 
Stigma terminating a long style : anther 1. ' 1. Za'nnichellia. 



stigma sessile : anthers 2. 



2. RUPPIA. 



stamens 4, the connectives with dilated appendages : drupelets sessile. 3, Potamogeton. 



1. ZANNICHELLIA L. 



Delicate submerged herbs, with filiform branching flaccid stems. Leaves alternate : 
blades slender, entire, 1-nerved, tapering from the dilated base. Flowers monoecious, both 
kinds in the same axils ; staminate of a single stamen : anther 2-4-ceiled, terminating a 
pedicel-like filament. Pistillate flowers consisting of a gynoecium of 2-6 sessile carpels.. 
Ovary flask -shaped : stigma peltate or somewhat cup-shaped, with uneven edges, surmount- 
ing a long style. Fruit a cluster of somewhat elongated curved stalked idrupelets, these 
ribbed, sometimes toothed on the back. Seed with a coiled embryo. 

1. Zannichellia paliistris L. Stems filiform, 2-7 dm. long, sparingly branched : 
leaves numerous ; blades soft, narrowly linear, 2-9 cm. long, acute, l-nerve^i : stipules or 
spathes persistent, separating from the leaves : peduncles very short : pedicels obsolete 
or wanting : drupelets 2-4, or sometimes 6 in a cluster, oblong or oblong-falcate, 2-4 mm. 
long, tipped with the persistent style, maturing under water. 

In fresh or brackish ponds or ditches, throughout North America, except the extreme north. 
Summer and fall. Also throughout the Old World. 



2. RUPPIA L. 



Submersed delicate herbs, with filiform branching stems and elongated rootstoeks. 



nerved 



basal sheath. Flowers perfect, terminating spadix-like peduncles. Perianth wanting. 
Stamens 2 : anthers sessile ; sacs large, separate, attached by their backs to the rachis. 
Pistils 4, sessile : stigmas sessile, peltate. Fruit a cluster of several oblique stipitate drupe- 
lets. Embryo with the hypocotyl and the inflexed cotyledonary end immersed. 

1. Ruppla marftima L. Foliage deep green. Stems slender, 3-10 dm. long, often 
whitish ; internodes unequal in length : leaf-blades narrowly linear, or filiform, 2.5-4 cm. 



ZANNICHELLIACEAE 37 

long, attenuate : sheaths membranous, 6-8 mm. long, each with a minute ligule : peduncles 
filiform, sometimes becoming 3 dm. long : drupelets ovoid, about 2 mm. long, oblique or 
gibbous at the base, 4-7 together, in umbel-like clusters, each on a stipe 1-4 cm. long. 

In salt or brackish water on the Atlantic and Pacitic coasts and in the interior of North America. 
Summer. Widely distributed throughout the world. Ditch-grass. 



6. P. Lonchites, 

7. P. Zizii. 



9. P. 2>€rfoli'at2CS, 
10. P. CurtimL 



3. POTAMOGETON L. 

Perennial submerged herbs, with more or less elongated often branching stems. Leaves 
commonly numerous, often of 2 kinds : submerged of thin texture : floating smaller, of 
thick texture. Spathe stipule-like, free, or united with the base of the petiole or blade, 
early deciduous. Peduncles axillary. Spikes mostly erect. Flowers perfect. Perianth 
wanting or obsolete. Stamens 4. Anthers sessile, the connectives bearing dilated appen- 
dages. Pistils 4, distinct, sessile : ovary 1-celled. Stigmas sessile or terminating recurved 
styles. Fruit of 4 drupelets with a hard or spongy pericarp. Seeds solitary, crustaceous, 
campylotropous. Embryo hooked. Poxdweed. 

Stipules axillary, free from the leaf. 

Plants with both submerged and floating leaves. 
Submerged leaves without blades. 

Floating leaves with ovate broadly elliptic or oval blades subcordate or rounded at the base : 

flowering spikes 3-6 cm. long, 5-6 mm. thick. 1. P. natans. 

Floating leaves with narrowly elliptic blades acute at both ends : flowering 

spikes 1-2 cm. long, 2.5-4 mm. thick. 2. P. Iloridanus, 

Submerged leaves with normal blades. 

Blades of submerged leaves of 2 forms. 3. P. pulchcr. 

Blades of submerged leaves all alike. 

Submerged leaves with linear or nearly linear blades. 

Leaf-blades with coarse cellular reticulation in the middle. 4. P. Nnttallii, 

Leaf-blades with inconspicuous cellular reticulation, 6. P. heterophyllus. 

Submerged leaves with lanceolate or oblanceolate blades. 
Leaf-blades distinctly petioled. 
Leaf-blades sessile or nearly so. 
Plants with submerged leaves only. 
Leaf-blades broad. 

Blades short-petioled or nearly sessile. 8. P. lucens. 

Blades clasping the stem. 
Leaf-blades linear or filiform. 
Blades 1-nerved. 

Blades 3-nerved. 

Drupelets crested : plants without propagating buds or glands. 11. P.foliosus. 

Drupelets crestless : plants with both propagating buds and glands. 12. P. pusUlus. 
Stipules adnate to the blades or the petioles of the submerged leaves. 

Plants with both submerged and floating leaves : drupelets crested. 13. P. diver sifoUus, 

Plants with submerged leaves only : drupelets crestless. 14. P. pectinatus, 

1- Fotamogeton nutans L. Stems 6-12 dm. long, simple or sparingly branched : 
leaves various, of 2 kinds, those of submerged leaves reduced to bladeless petioles which 
perish early ; those of floating leaves with leathery ovate broadly elliptic or oval blades 4-9 
cm.^ long, usually abruptly pointed, many-nerved, rounded or subcordate at the base ; 

f)etioIes as long as the blades or much longer: peduncles as thick as the stem, 4-9 cm. 
ong : spikes cylindric, 3-6 cm. long, dense : drupelets narrowly obovoid, 4-4.5 mm. long, 
scarcely keeled : nutlets more or less pitted on the sides, 2-grooved on the back. 

In still water or streams, nearly throughout North America; Also in Europe and Asia. Summer. 

2. Potamogeton FlorideUius Small. Resembling P. natans^ but more slender. 
Floating leaves few ; blades narrowly elliptic, 4-7 cm. long, acute at both ends, narrowly 
revolute, with 7 main nerves ; petioles v.ery slender, several times longer than the blades : 
peduncles stouter than the stem, 4-6 cm. long: flowering spikes cylindric, 1-2 cm. long, 
2,5-4 mm. thick. 

In the Blackwater River, Florida. Spring and summer. 

3. Potamogeton ptilcher Tuckerm. Stems 3-6 dm. long, nearly simple, terete, 
spotted : leaves various ; blades of 3 kinds, those of submerged leaves leathery, spatulate 
ovate or oblong, and those above these flimsy, pellucid, lanceolate, 8-20 cm. long, attenu- 
ate, short-petioled ; those of floating leaves leathery, ovate or orbicular-ovate, 4-10 cm. long, 
obtuse or abruptly pointed, many-nerved, cordate at the base ; petioles as long as the blades 
or longer : peduncles slightly thicker than the stem, 5-10 cm. long : spikes cylindric, dense, 
2-2.5 cm. long : drupelets turgid, 4-4.5 mm. long, abruptly pointed, 3-keeled on the back. 

In ponds. Maine to Missouri and Georgia. Summer. 



4. Potamogeton Nuttdllil Cham. & Schlecht. Stem slender, 3-20 dm. long, flattened, 
simple or sparingly branched : leaves various ; blades of 2 kinds, those of submerged leaves 
linear, 2-ranked, 5-16 cm. long, 5-nerved, reticulated between the midrib and contiguous 



38 ZANMCHELLIACEAE 



nerves ; those of floating leaves leathery, oblong, elliptic orobovate, 3-8 cm. long, many- 
nerved, short-petioled : peduncles 2.5-12 cm. long : spikes 1.5-2 cm. long, dense, emersed 
or partly so: drupelets globose -obo void, 2.5-3 mm. long, 3-keeled, the middle keel sharp: 

embryo coiled IJ times. 

In ponds and streams, Nova Scotia to Ontario and South Carolina. Summer. 

5. Potamogeton heterophyllus Schreb. Stems slender, 1-3.5 m. long, flattened, 
branched : leaves various ; blades of 2 kinds, those of submerged leaves lanceolate or nar- 



rowly linear-lanceolate, 2.5-8 cm. long, mostly sessile, with conspicuous cellular reticula- 
tions; those of floating leaves leathery, oval or elliptic, 1.5-4 cm. long, abruptly pointed, 
shorter than the petioles : peduncles 2.5-15 cm. long, often thickened upward : spikes 2-4 
cm. long, dense : drupelets nearly as broad as long, 1.5-3 mm. long, indistinctly 3-keeled 
on the back, abruptly pointed. 

In still or flowing water, nearly throughout North America. Also in Europe. Summer and fall. 

6. Potamogeton Lonchites Tuckerm. Stems terete, 9-20 dm. long, branching : 
leaves various ; blades of two kinds ; those of submerged leaves elongated, lanceolate or 
oblanceolate, 10-30 cm. long, pellucid ; those of floating leaves thinnish, oblong or ellip- 
tic, 4-15 cm. long, many-nerved, usually acute at both ends ; petioles fully J as long as the 
blades: peduncles 5 cm. . long, slightly thickened upward: spikes cylindric, 2.5-5 cm. 
long, dense : drupelets as broad as long, 3.5-4 mm. long, 3-keeled on the back, the middle 
keel prominent. 

In ponds and rivers, New Brunswick to Washington, Florida and California. Summer and fall. 

7. Potamogeton Zizii Roth. Stems slender, elongated, branching : leaves various ; 
blades of 2 kinds ; those of submerged leaves lanceolate to oblanceolate, 5-15 cm. long, cus- 
pidate or acute, wavy- margined, pellucid; those of floating leaves more less leathery, 
elliptic, 3-10 cm. long, many-nerved, sessile or nearly so: peduncles thicker than the 
stems, 5-15 cm. long : spikes 2.5-5 cm. long, not very dense ; drupelets nearly as broad as 
long, 2.5-3.5 mm. long, 3-keeled on the back, abruptly pointed. 

In lakes and rivers, Quebec to Montana, Florida, Texas and Wyoming. Summer. Also in Europe. 

8. Potamogeton lucens L. Stems stout, elongated, more or less branched, often 
profusely so above : leaves all submerged ; blades elliptic or lanceolate, or oval above, 
5-20 cm. long, acute or acuminate or sometimes mucronate, often serrulate at the apex, 
mostly 13-nerved, short-petioled or nearly sessile : peduncles 7-15 cm. long, barely thick- 
ened upward : spikes dense, 5-7 cm. long : drupelets 3 mm. long, blunt-tipped. 

In ponds, Nova Scotia to California, Florida and Mexico. Fall. Also in Europe, 

9. Potamogeton perfoliitus L. Stems slender, elongated, much branched : leaves 
all submerged ; blades suborbicular to ovate or lanceolate, 2-4 cm, long, usually obtuse, 
often serrulate at the apex, cordate-perfoliate, crisped : peduncles 2.5-3.5 cm. long, about 
as thick as the stem: spikes 1.5-2.5 cm. long, as long as the peduncle or shorter, often 
fruiting under water: drupelets obliquely obovoid, 2.5-3 mm, long, obscurely 3-keeled on 
the back. 

In rivers and ponds. Newfoundland to British Columbia, Florida and California. Also in Europe. 
Summer and fall. 

+ 

10. Potamogeton Curtissii Morong. Stems delicate, filiform, 2-4 dm. long, simple 
or branched ; internodes elongated, naked : leaves all submerged : blades linear-filiform, 
1-4 cm. long, 0.5-1 mm. broad, terminating in a hair-like tip, 1-nerved, sometimes with an 
indication of 2 lateral nerves ; stipules hyaline, 6-8 mm. long, obtuse, deciduous : pedun- 
cles slender, club-shaped, 6-12 mm. long, erect, axillary near the upper end of the stem : 
spikes capitate, 4-6 mm. long, 3-6-flowered : fruit not seen. 

In tidal creeks, Blackwater River, Florida. Spring and summer. 

11. Potamogeton foliosus Kaf. Plants without propagating buds, or glands at the 
base of each leaf. Stems 3-10 dm. long, flattened, much branched : leaves all submerged, 
very numerous ; blades linear or filiform, 1.5-5 cm, long, acute, 3-nerved : peduncles some- 
what club-shaped, 8-12 mm. long: spikes short, about 4-flowered : drupelets 1.5-2 mm. 
long, 3-keeled; middle keel crest-like, undulate or sinuate-toothed, often with tooth-like 
shoulders at each end. 

In streams and ponds, New Brunswick to British Columbia, Florida and California. Summer. 

12. Potamogeton pusillus L. Plants with both propagating buds and glands at the 
base of each leaf. Stems filiform, 1-6 dm. long, branched : leaves all submerged, numer- 
ous ; blades linear or linear-filiform, 2-8 cm. long, acute, 1-3-nerved, usually 2-glandular 
at the base : peduncles slender, 6-20 mm. long, or rarely 10 cm. long : spikes 3-10-flowered, 
capitate or interrupted : drupelets longer than broad, 1.5-2 mm. long, 2-grooved on the 
back or with 3 distinct keels, crestless. 

In slow streams and ponds, New Brunswick to British Columbia, North Carolina, Texas and Cali- 
fornia. Summer, Also in Europe. 



NAIADACEAE 



39 



13. Potamogeton diversifollus Eaf. Stems elongated, flattened or nearly terete, 
branched : leaves various ; blades of 2 kinds ; those of submerged leaves linear-setaceous, 
2-8 cm. long, acute, 1-nerved ; those of the floating leaves leathery, elliptic or oval, some- 
times oblong-lanceolate, 1-2.5 cm. long, obtuse or acute : petioles shorter than the blades 
or rarely longer : peduncles various, emersed club-shaped, 6-14 mm. long ; submerged, 4-6 
mm. long : spikes dense, 4-8 mm. long : drupelets cochleate, about 1 mm. long, 3-keeled ; 
middle keel crest-like, 7-8-toothed ; lateral keels acute or obtuse. 

In pools and still water, Maine to Montana, Florida and Texas. Spring and summer. 

14. Potamogeton pectin^tus L. Stems slender, 3-10 dm. long, or longer, repeat- 
edly forking : leaves all submerged ; blades setaceous or filiform, 2-15 cm. long, 1-nerved 
or nerveless : peduncles filiform, 5-30 cm. long : spikes interrupted, sometimes elongated ; 
flowers in approximate whorls or these remote : drupelets cochleate, barely fleshy, 1.5 mm. 
long, 3-keeled on the back, crestless, but with 4-5 teeth. 

In still or running fresh or salt water, Cape Breton Island to British Columbia, Florida, Texas and 
California. Summer and fall. 



Family 2. ZOSTERACEAE Dumort. Eel-grass Family. 

Perennial marine herbs, with creeping rootstocks and flattened branching 
stems. Leaves alternate, 2-ranked : blades several-nerved, linear from a 
sheathing inflated base. Flowers monoecious, both kinds arranged alternately 
on a flattened spadix ; this enclosed in a spathe. Perianth wanting. Stami- 
nate flower a sessile 1-celled anther attached to the spadix. Pollen thread-like. 
Pistillate flower a single pistil with an elongated style and 2 thread-like stigmas, 
attached by its back to the spadix. Fruit a flask-shaped beaked utricle ; this 
irregularly rupturing. Seeds ribbed : embryo ellipsoidal. 



1. ZOSTERA L. 

Characters of the family. Eel-grass. Grass- wrack. 

Leaves 0.5-1.5 dm, long, 1-nerved : seeds 1.5 mm. long. 1, Z. minor. 

Leaves 2-18 dm. long, 3-7-nerved : seeds 3 mm. long. 2. Z, marina, 

1. Zostera minor (Caval.) Nolte. Stems more or less elongated, often sparingly 
branched. Leaves few ; blades narrowly linear, 0.5-1.5 dm. long, obtuse, 1-nerved, usually 
about 1-5 mm. broad : spathe 1-1.5 cm. long : fruits flask-shaped, with an oval or broadly 
oblong body in all about 3 mm. long, 4-5 maturing in a spathe : seeds nearly 1.5 mm. long, 
smooth or very faintly striate. 

In shallow water. Key West, Florida. Also in Europe. 

2. Zostera marina L. Stems slender. Leaf-blades linear, ribbon-like, 2-18 dm. 
long, obtuse, 3-7-nerved: spadix 2.5-6.5 cm. long: flowers commonly 10-20 on each 
spadix : fruits oblong, fully 3 mm. long, obtuse : seeds nearly cylindric, about 3 mm. long, 
20-ribbed, truncate. 

In streams or ditches, on or near the coast. Greenland and Labrador to Florida, also from Alaska 
to California, and on the coasts of Europe. Summer. 

1 

F 

Family 3. NAIADACEAE Lindl. Naias Family. 

Submerged herbs, with fibrous roots and slender branching stems. Leaves 
alternate, opposite or whorled : blades various, dilated and sheathing at the 
base, mostly toothed. Flowers dioecious, solitary in the axils. Staminate flow- 
ers with a double perianth, the outer entire or 4-horned, the inner hyaline, ad- 
hering to the solitary stamen. Anther sessile or short-stalked j 1-4-celled, apic- 
ulate or 2-lobed at the apex. Pistillate flowers with a single ovary, topped by a 
short style and 2-4 stigmas. Fruit a sessile drupelet, with acrustaceous pericarp 
and a membranous epicarp. Seed solitary, filling the pericarp. Embryo con- 
formed to the interior of the seed. 



Characters of the family. 



1. NAIAS L. 



Sheaths oblique, with margins minutely 10-20-toothed. 
Leaf-margins with shallow inconspicuous teeth. 

Pericarp of the drupelets dull, with 16-20 rows of strong reticulations : leaf- 
blades with 80-100 marginal teeth. 
Pericarp of the drupelets shining, with 30-50 rows of delicate reticulations : 

leaf-blades witn 50-60 marginal teeth. 



1. N, Guailalupcnsis, 

2. iV. flexiUs. 



40 



SCHELTHZERIACEAE 



Leaf-margins with prominent sharp teeth. 3. X. con/erta. 
Sheaths equilateral, with margins entire or coarsely few-toothed. 

Leaves about 0.5 mm. broad, with 15-24 marginal teeth : internodes filiform. 4. K gracilis. 

Leaves about 2 mm. broad, with 6-10 marginal teeth : internodes stout. 5. N. marina, 

1. Naias Guadalup^nsia (Spreng. ) Morong. Stems filiform or hair-like, 3-7 dm. 
long, widely branched: leaves opposite, sometimes clustered; blades narrowly linear, 
10-20 mm. long, acute, often curved, with 40-50 minute teeth on each margin : drupelets 
2 mm. long ; pericarp granular, marked with 16-20 rows of rectangular or hexagonal reticu- 
lations, the long axis transverse. [iV. microdon A. Br.] 

In ponds and lakes, Nebraska to Oregon, Florida, Texas and throughout^tropical America. Sum- 
mer and fall. 

2. Naias £16xilis (AVilld. ) Eostk. & Schmidt. Stems slender, 2-18 dm. long, forking ; 
internodes commonly armed with teeth : leaves numerous ; blades narrowly linear, 1-2.5 cm. 
long, acute or acuminate, with 25-30 minute teeth on each margin : drupelets ellipsoidal, 
2-4 ram. long ; pericarp lustrous, finely sculptured, with 30-50 rows of square or hexagonal 
reticulations. 

In streams and ponds, nearly throughout North America. Summer. Also in Europe. 

3. Naias conf^rta A. Br. Similar to y. jlexUU in habit. Leaves slender, the mar- 
gins with prominent sharp teeth. 

In tidal creeks, Milton, Florida. Summer. Also in tropical America. 

4. Naias grdcilis (Morong) Small. Stems filiform, forking ; branches erect or as- 
cending, the internodes 2.5-10 cm. long, with a few teeth near the upper ends : leaves 
slender ; blades 2-4 cm. long, about 0.5 mm. broad, with 15-24 marginal teeth and few 
dorsal teeth : sheaths with 2-3 teeth on each margin : drupelets barely 4 mm. long, slightly 
oblique ; pericarp with about 25 rows of square or irregular-oblong reticulations. \^N, 
marina var. gracilis Morong.] 

In creeks and ponds, Florida. Spring to winter. 



5. Naias marina L. Stems stout, several dm. long, flattened, branching, commonly 
armed with tooth-like spines about twice as long as broad : leaves opposite or whorled ; 
blades linear, 10-25 mm. long, about 2 mm. wide, acute, with 6-10 spine-like teeth on 
each side and sometimes several on the back of the midrib : drupelet oblong, 4-5 mm. 
long; pericarp granular, reticulated. \_N, major All,'] 

In lakes, New York to California and Florida. Summer. Also in Europe. 

Order 3. ALISMALES. 

Marsh or aquatic herbs, with rush-like or spongy tissues. Leaves alternate, 
various, slender and stiff, or with dilated blades. Flowers perfect, monoecious 
or dioecious. Perianth of 2 often dissimilar series (sepals and petals). Androecium 
of 3-6 stamens. Gynoecium of 3-mauy distinct carpels. Endosperm wanting. 

Petals nearly similar to the sepals : anthers long and narrow : carpels coherent. 

^ , Fam. 1. SCHEUCHZERIACEAE. 

Petals very different from the sepals : anthers short and thick: carpels 

not coherent. Fam. 2. Alismaceae. 

Family 1. SCHEUCHZERIACEAE Agardh. Arrow-grass Family. 

Perennial marsh herbs, with scapes or normal stems. Leaves alternate : 
blades rush-like, narrow, often very slender from a dilated ba^^e. Flowers per- 
fect, in teiminal spikes or racemes : perianth of 4-6 members in 2 series, or the 
corolla wanting, persistent or deciduous. Androecium mostly of 4-6 stamens. 
Filaments variable in length. Anthers usually 2-celled, extrorse. Gynoecium 
of 3-6 partially united carpels. Stigmas sessile or nearly so. Ovules 1 or 2 in 
each cavity, anatropous. Fruit of 3-6 separating dehiscent or indehiscent 
carpels. Seeds 1 or 2 in each carpel. Embryo straight. 



1. TRIGLOCHIN L. 



A caulescent marsh herbs, 



dilated 



aaonly with abbreviated rootstocks. Leaves basal, 
nembranous bases : blades narrow, elongated. Scapes 
slender, erect, simple. Spikes or racemes terminal. Perianth inconspicuous : sepals 3 : 
petals 3, remote from the similar sepals, or wanting. Stamens 3-6 : anthers 2-celled, sessile 
or nearly so. Pistils 3-6, 1 -celled : stigmas 3-6, sessile or nearly so, plumose. Ovule soli- 



ALISMACEAE 



41 



tary, erect. Carpels leathery, 3-6, distinct or partially united until fully mature, each 
opening by a ventral suture. Seeds solitary, erect, flattened or angled. 

1. Triglochin striata R. & P. Foliage' glabrous. Leaves basal; blades slightly 
fleshy, linear, attenuate, 0.5-2 mm. broad, 2-3 dm. long, erect: scapes erect, solitary or 

2 together, angled, about as long as the leaves or longer ; racemes 2-15 cm. long, barely if 
at all interrupted : pedicels 1-1.5 mm. long, not crowded : perianth greenish or light yel- 
loM' : sepals 3, oval or ovate, obtuse, less than 1 mm. long : stigmas plumose : fruit sub- 
globose, 1.5-2 mm. in diameter, somewhat o-winged at maturity : carpels 3, 3-ribbed on 
the back. \_TriglocJiin iriandra Michx.] 

In salt marshes, Maryland to Florida and Louisiana. Summer and fall. Arrow-guass. 

Family 2. ALISMACEAE DC. Water-plaxtain Family. 

Annual or perennial acaulescent aquatic or marsh herbs. Leaves basal : 
petioles elongated, sheathing at the base : blades flat, several-ribbed, often with 
spreading or deflexed lobes. Scapes erect or floating, mostly simple to the in- 
florescence. Flowers perfect, monoecious or dioecious, regular, whorled, dis- 
posed in terminal racemes or panicles. Receptacle flat or globose. Calyx of 

3 persistent sepals. Corolla white or pink, of 3 deciduous imbricated petals. 
Androecium of 6 or more stamens. Filaments distinct. Anthers 2-celled, 
extrorse. Gynoecium of few^ or many carpels. Ovaries 1-celled. Styles rather 
persistent. Ovules solitary in each cavity. Fruit a head of flattened achenes. 
Seeds cnrved. Embryo horseshoe-shaped 

Carpels in a ring on a flat receptacle. 1. Altsma. 
Carpels curved in many series on a convex or globose receptacle. 
Flowers perfect or polygamous. 

Sepals spreading : pedicels not recurved at maturity. 2. Echinodori's. 

Sepals appressed : pedicels recurved at maturity. ' 3. Lophotocakpcs. 

FloM'ers monoecious or dioecious, ' 4, Sagittaria. 

1. ALiSMA L. 

Annual, or mostly perennial scapose herbs. Leaves erect or floating : blades several- 
ribbed, without basal lobes, narrowed into petioles. Flowers perfect, in compound or 
umbel-like panicles. Stamens 6-9, rather perigynous : filaments slender. Carpels few or 
many, in one whorl on a flat receptacle. Achenes in 1 whorl, 2-3-ribbed on the back, 
1-2-ribbed on the sides. Water Plantain, 

1. Alisma subcordktum Eaf. Perennial, glabrous or nearly so. Leaf-blades ob- 
long, elliptic, oval or ovate, or sometimes narrower, 3-15 cm. long, usually abruptly 
pointed, entire, cuneate to truncate, or cordate at the base ; petioles often longer than the 
blades : scapes 1-10 dm. tall, solitary or several together ; branches and pedicels in whorls 
of 3-10, variable in length : bracts lanceolate or linear, often acuminate : sepals broadly 
ovate to suborbicular, obtuse : petals white or pinkish, 1-2 mm. long : mature heads 4-6 
mm, broad, flat : achenes obliquely obovate, 2 mm. long; beak small, ascending. 

In swamps and shaUow water. Nova Scotia to North Dakota, Florida and Texas, Spring to fall. 

2. ECHINODORUS L. C. Rich. 

Annual or perennial usually acaulescent marsh herbs. Leaves erect or ascending: 
blades sometimes ample, several-ribbed. Scapes usually surpassing the leaves. Flowers 
perfect, in whorls disposed in racemes or panicles. Stamens 12-30 : filaments often about 
as long as the anthers. Carpels numerous, inserted on a convex or globose receptacle. 
Style obliquely apical : stigma simple. Achenes forming a bristly head, leathery, ribbed, 
and beaked by the persistent style. 

Carpels few, usually less than 14 naaturing : flowers in terminal umbel-like clusters. 1. E, parvulus. 
Carpels numerous, many maturing: flowers in terminal panicles, the main axis of 
the panicle sometimes greatly elongated. 
Scapes creeping near the base : stvle shorter than the ovary : beak about 34 ^ lo"& 

as body of the achene. 
Scapes erect or ascending : style longer than the ovary : beak fully % as long as 

body of the achene. 



2. E. radicans. 



S. E, cardifolius. 



1- Echinodonis pdrvulns Engelm. Leaf-blades linear to linear-elliptic, 1-3 cm. 
^ong, acute at both ends, longer than the petioles or much shorter : scapes solitary or 



several together, surpassing the leaves or overtopped by them, topped by a whorl of 2-8 
pedicels, these spreading or curved, 5-25 mm. long, unequal 



in length : bracts white, 



42 



ALISMACEAE 



3-5 mm. long : petals white : mature heads 3-4 mm. in diameter : achenes broadly and 
obliquely obovate, barely 1 mm. lon^, black ; beak minute, sharp, oblique. 

In mud, Massachusetts to Ontario and Minnesota, Florida and Texas. Spring to fall. 

2. Echinodorus radicans (Xutt. ) Engelm. Leaf -blades ovate or oblong, 5-20 cm. 
long, obtuse, undulate, truncate or cordate at the base ; petioles 1-7 dm. long : scapes 
elongated, spreading or decumbent, creeping, 3-12 dm. long, often solitary : whorls of the 
inflorescence remote : pedicels 3-12, unequal, 1.5-6 cm. long : bracts linear-lanceolate 
from dilated bases : sepals ovate or orbicular-ovate, rather obtuse : petals white, about 
6 mm. long : mature heads bur-like, 7-8 mm. in diameter : achenes cuneate, 2 mm. long ; 
body 6-10-ribbed ; beak about ^ as long as the body. 

In ponds and swamps, Illinois and Missouri, to Florida and Texas. Spring and summer. 

3. Echinodorus cordifollus (L. ) Griseb. Leaf-blades various, lanceolate to broadly 
ovate, 4-20 cm. long, obtuse, commonly truncate or cordate at the base ; petioles angled, 
usually longer than the blades: scapes solitary or clustered, 1-5 dm. tall, surpassing the 
leaves, simple or branched from the lower whorls of the inflorescence : pedicels 7-15 mm. 
long, not very variable in length : bracts lanceolate or linear-lanceolate : sepals ovate, 
rather acute : petals white, 4-6 mm. long, usually broader : mature heads bur-like, 4-6 
ram. in diameter : achenes 2.5-3 mm. long ; body cuneate ; beak slender, fully i as long 
as the body. \_E. rostratus Engelm.] 

In ditches and swamps, Illinois and Missouri, to Florida and Texas. Spring and summer. 

3. LOPHOTOCARPUS T. Durand- 

Annual or perennial acaulescent aquatic or marsh herbs. Scapes simple below the 
inflorescence. Flowers in several whorls of 2-3 at the top of the scape ; upper staminate ; 
lower pistillate. Stamens 9-15, hypogynous : filaments flattened, inserted at the base of 
the receptacle. Pistils numerous on a convex receptacle. Style slender, oblique. 
Achenes crowded together, crested or winged, more or less completely enveloped by the 
calyx. Embryo horseshoe-shaped. 

Petioles 0.5-1.5 dm. long : leaf-blades less than 4.5 cm. broad : whorls of the inflorescence usually soli- 
tary : mature fruiting heads 7-8 mm. in diameter. 1. L. depauperatus. 

Petioles 1.5-4 dm. long : leaf-blades over 4.5 cm. broad : whorls of the inflorescence 

2-6 : mature fruiting heads 10-15 mm. in diameter. 2. X. calycinus. 

1. Lophotocarpus depauperktus J. G. Smith. Leaves with petioles 0.5-1.5 dm. 
long ; blades oblong, elliptic, oval or ovate, sometimes sagittate or hastate, 1-2 cm. wide 
or the small basal lobes spreading to a w^idth of 3-4 cm. and acuminate : inflorescence of 
usually 1 whorl : mature fruiting heads 7-8 mm. in diameter: achenes cuneate, about 1.7 
mm. long, each Avith a slender horizontal beak. 

On margins of ponds, Wisconsin, Illinois, Missouri and the Indian Territory. Summer and fall. 

2. Lophotocarpus calycinus (Engelm.) J. G. Smith. Leaves with petioles 1.5-4 
dm. long ; blades hastate or sagittate, sometimes almost triangular or lunate, the basal 
lobes often longer than the middle one, spreading to a width of 5-30 cm. and^ usually 
acuminate: inflorescence of 2-6 whorls : mature fruiting heads 10-15 mm. in diameter: 
achenes cuneate, 2-2.5 mm. long, each with a triangular horizontal beak. iSagitiaria caly- 
cina Engelm.] 

In swamps or ponds, often submerged. South Dakota to Delaware, Louisiana and New Mexico. 
Summer. 

4. SAGITTARIA L. 

Perennial acaulescent marsh or aquatic herbs, either erect or floating. Kootstock 
irregularly thickened or tuber-bearing. Leaves various, usually differentiated into petioles 
and blades, or reduced to pliyllodes. Scapes sometimes greatly elongated, usually simple 
below the inflorescence. Flowers monoecious or dioecious, in whorls of 3 near the top of 
the scape, those of the upper whorls usually staminate. Staminate flowers with many 
stamens : anthers 2-celled, opening by lateral slits : gynoecium wholly or partially sup- 
pressed. Pistillate flowers with many distinct carpels : androecium wholly or partially 
suppressed. Keceptacle more or less convex. Achenes numerous, flattened, densely 
crowded in globular heads. Arrow-head. 

Sepals of the pistillate flowers reflexed or spreading, not accrescent. 
Pedicels of the pistillate flowers much thickened, reflexed at maturity. 
Filaments glabrous. 
Scapes simple. 

Filaments about as long as the anthers : achenes with 3 undulate or slightlj' toothed crests. 

1, S. subnlata. 



ALISMACEAE 



43 



\ 



Filaments much longer than the anthers : achenes with 5-7 crenate 
or dentate crests. 
Scapes branching. 
Filaments pubescent. 
Pedicels of the pistillate flowers slender, ascending, or wanting. 
Leaf-blades entire or barely hastate, sometimes greatly reduced. 
Pistillate flowers pedicelled. 
Filaments dilated. 

Pedicels of the pistillate flowers shorter than those of the stam- 
inate. 

Pedicels of the pistillate flowers as long as those of the staminate 
or longer. 

Leaves terete, mostly bladelcss. 

Filaments as long as the anthers : achenes 1 mm. long, with 
low facial ridges. 

Filaments shorter than the anthers: achenes 2mm. long, 
with several facial wings. 
Leaves with more or less flattened blades. 
Achenes oval or broadly oblong. 
Achenes cuneate. 

Beak large, horizontal at the top of the achene. 
Beak minute, much below the top of the achene. 
Bracts ovate, united to the middle. 
Bracts lanceolate, nearly distinct. 
Filaments slender, not dilated. 
Filaments glabrous. 

Bracts ovate, obtuse, united to about the middle : beak near 

the middle of one side of the achene. 
Bracts lanceolate, acuminate, distinct or nearly so : beak hori- 
zontal at top of the achene. 
Filaments pubescent. 
Pistillate flowers sessile. 
Leaf-blades mostly sagittate. 

Basal lobes twice or thrice as long as the middle lobe. 
Basal lobes shorter than the middle lobe. 

Pedicels of the pistillate flowers much shorter than their bracts. 
Pedicels of the pistillate flowers surpassing their bracts. 
Filaments villous, not dilated : bracts and sepals viscid. 
Filaments glabrous: bracts and sepals not viscid. 

Beak of the achene erect, the tip sometimes recurved. 

Lobes of the leaf-blades ovate, obtuse : achenes broadest at 

the top with 1 facial wing on each side. 
Lobes of the leaf-blades linear or nearly so, acute : achene 
broadest at the middle with 2 facial wings on each side. 
Beak of the achene lateral, horizontal or oblique. 

Foliage, especially that of the inflorescence, glabious. 
Foliage, especially that of the inflorescence, pubescent. 
Sepals of the pistillate flowers erect, accrescent. 



2. S, vatans. 

3. S. flUforrnfs, 

4. S. platyphylla. 



5. S, macrocarpa. 



6. S. isocUformis. 

7. S. teres, 

8. 5. cydoptcra. 

9. S. MohriL 

10. *^. graminea, 

11. S Chapmanii, 



12. S.*pnpilIosa, 

13. 5. amhif/iia. 

14. S. lancifolia. 

15. 5. rig Ida, 

16. S, longiloha, 

17. S, longirostra, 

18. S, viscosa. 



19. S. aiistralis, 

20. S, Engelmanniana 

21. 5. iaUfoUcu 

22. S, pubcscens. 

23. S. Montevidensis. 



1. Sagittaria subul^ta (L. ) Buch. Monoecious or sometimes wholly staminate. 
Leaves usually represented by rigid phyllodes 2-12 cm. long, rarely normal ; blades linear 
to linear-lanceolate, 2-3 cm. long, acutish, shorter than the petioles : scapes 5-15 cm. tall, 
rarely surpassing the leaves : whorls of the raceme solitary or often 2 : bracts thin, 1-3 
mm. long: pedicels of pistillate heads 10-15 mm. long: sepals ovate-lanceolate, obtuse: 
corollas 15 mm. broad : achenes few, 1.5 to nearly 2 mm. long, with short lateral beaks 
and 3 prominent but merely undulate or sparingly toothed crests. 

In mud and tidal flats, New York to Florida and Alabama. Summer and fall. 

2. Sagittaria nutans Michx. Monoecious, commonly submerged. Petioles blade- 
less, or blades floating, elliptic, oblong or ovate-oblong, 1.5-5 cm. long, rounded, subcor- 
date or hastate-truncate at the base : phyllodes flattened, elongated : scape elongating to 
the surface of the water or rising above it, 1-10 dm. long : whorls of the inflorescence one 
or several : bracts thin, acuminate : mature fruiting heads 8 mm. in diameter : achenes 
rather numerous, 2 mm, long, with short upcurved beaks and 5-7 prominently dentate or 
crenate crests. 

In fresh or brackish ponds, South Carolina to Florida. Summer and fall. 

3. Sagittaria filifdrmis J. G. Smith. Monoecious, submerged. Leaves wanting : 
phyllodes filiform from thicker bases, 1-6 dm. long, rarely as long as the scape : scapes 
slender, 6-12 dm. long, often branching from the lower whorls : bracts lanceolate, 3-5 mm. 
long, acuminate : pedicels filiform, those of the lower whorls 1^ cm. long, ascending or 
erect: whorls remote, staminate except 1 or 2 flowers of the lower one: sepals ovate, 2-3 
inm. long, obtuse : corolla white, about 2 cm. broad : mature fruiting heads 6-7 mm. in 
diameter : achenes 1.5 ram. long, with upcurved lateral beaks and about 6 crests. 

In ponds, Florida and Alabama. Spring and summer. 

4. Sagittaria platyphylla (Engelm. ) J. G. Smith. Monoecious. Leaf-blades rather 
leathery, lanceolate, elliptic to ovate, 5-15 cm. long, 5-7-nerved, acute or acuminate, 
gradually narrowed or subcordate at the base : scapes 2-5 dm. tall, usually overtopped by 



44 



ALISMACEAE 




the leaves : whorls of the inflorescence 3-8, tlie 2 or 3 lower ones pistillate : pedicels 1-2.5 
cm. long : bracts broadly ovate, 3-8 ram. lonj?, scarious tipped : mature fruiting heads fully 
1 cm. in diameter : achenes obliquely obovate, 2 mm. long, winged ; beak horizontal. 

In ponds and swamps, Missouri to Alabama and Texas. Spring to fall. 

5. Sagittarla macrocArpa J. G. Smith. Monoecious. Leaves phyllode-like; l)lades 
linear or linear-lanceolate, 5-7 cm. long, much shorter than the petioles : scapes 3-4 dm. 
tall, overtopping the leaves : whorls of the inflorescence 3-5, the lower pair, or only the 
lowest one, pistillate : pedicels about as long as the internodes except those of the pistillate 
flowers ; these much shorter : bracts obovate, 3 mm. long, acute, united at the base : fila- 
ments dilated, pubescent : mature fruiting heads 10-12 mm. in diameter: achenes obovate 
or oblong-ovate, 3 mm. long, winged ; beak ascending. 

On the margins of ponds, North Carolina and South Carolina. Spring to fall. 

6. Sagittarla iaoetifonxiis J. G. Smith. Monoecious, delicate. Leaves terete 
throughout, or rarely with imperfect flattish blades : scapes 8-12 cm. tall, as long as the 
leaves or overtopping them : whorl of the inflorescence usually one : bracts ovate, 2-3 mm. 
long, acute, united below : pedicels of pistillate flowers slender, 15-18 mm. long, those of 
the staminate flowers filiform, 2-3 cm. long : sepals 2 mm. long : corolla w^hite, 12-15 mm. 
broad : filaments dilated, pubescent, about as long as the anthers : mature fruiting heads 
about 6 mm. in diameter : achenes obovate, 1 mm. long, with a prominent dorsal crest 
and low facial ridges ; beak short, oblique. 

On sandy margins of lakes, peninsular Florida. Spring and summer. 

7. Sagittaria thies S. Wats. Monoecious, slender. Leaves usually reduced to 
terete attenuate nodose phyllodes 1-3 dm. long, or rarely developing narrow, imperfect 
blades at the top : scapes slender, 15-45 cm. tall : bracts ovate, 3 mm. long, obtuse : 
whorls of the inflorescence solitary or sometimes 3, 1 or 2 pedicels of the lower whorls 
bearing pistillate flowers, 10-25 mm. long, longer than those of staminate flowers : sepals 
about 3 mm. long : corolla Avhite, 12-15 mm. broad : stamens often 12 : filaments dilated, 
pubescent, shorter than the anthers : mature fruiting heads 8-12 mm. in diameter : achenes 
oval or oval-obovate, 2 mm. long, with stout obliquely upcurved beaks, an uneven crest 
and several facial wings. 

In shallow water, Massachusetts to South Carolina. Summer and fall. 

8. Sagittaria cycldptera (J. G. Smith) C. Mohr. Monoecious or dioecious. Leaves 
sometimes reduced to slender tapering phyllodes ; blades linear or linear-lanceolate, 4-15 
cm, long, tapering to both ends, shorter than the petioles : scapes 2-8 dm. long : whorls of 
the inflorescence 3-15, or rarely solitary, several of the lower ones usually pistillate : bracts 
ovate, 3-5 mm. long, acute, united at the base : filaments dilated, pubescent : mature fruit- 
ing heads barely 1 cm. in diameter : achenes broadly oblong or oval, 1.5 mm. long, winged, 
crested, with 2 facial wings on each side ; beak short, ascending, rather lateral. 

In swamps. South Carolina to Florida and Louisiana. Spring to fall. 

9. Sagittaria M5hrli J. G. Smith. Monoecious. Leaves 3-7 dm. tall ; blades linear 
to lanceolate, 5-15 cm. long, acuminate, often poorly developed : scapes ascending, decum- 
bent or declining, 3-angled : whorls of the inflorescence 6-8, the lower 3-4 pistillate, with 
pedicels somewhat lonj^erthan those of the staminate flowers : bracts thin, 3-4 mm. long, 
united to about the middle : sepals oblong, 2-3 mm. long, obtuse : corolla hardly 1 cm. 
broad : mature fruiting heads subglobose, 6-8 mm. in diameter : achenes cuneate, 2.5-3.5 
mm. long, winged, with cuneate crests ; beak horizontal. 

In muddy ponds, southern Alabama. Smnmer. 

10. Sagittaria graminea Michx. Monoecious or dioecious. Leaf-blades linear, 
lanceolate or elliptic, 5-15 cm, long, or leaves represented by phyllodes : scapes 1-6 dm. 
tall, shorter than the leaves or overtopping them : whorls of the inflorescence few and 
remote or sometimes numerous and rather approximate : pedicels variable, but those of 
staminate and pistillate flowers often equal in length : bracts ovate, 3-5 mm. long, acute, 
united to about the middle : filaments dilated, pubescent : mature fruiting heads less than 
1 cm. in diameter : achenes cuneate, 1.5 mm. long, winged, with one facial wing or crest; 
beak short, lateral, spreading. 

In mud or ponds, Newfoundland to Saskatchewan. Florida and Texas. Summer and fall. 

11. Sagittaria Chapmdnil (J. G. Smith) C. Mohr. Monoecious or dioecious. 
Leaves often accompanied by phyllodes ; blades linear or lanceolate, 15-20 cm. long, 
acute, usually much shorter than the petioles : scapes 3-5 dm. long : whorls of the inflores- 
cence often numerous : pedicels spreading or ascending, those of the pistillate heads 1.5-3 
cm. long : bracts lanceolate, 6-12 mm. long, acute or acuminate, slightly united at the 
base : filaments dilated, pubescent : mature fruiting heads 5 mm. in diameter : achenes 
cuneate, 1 mm. long, wingless ; beak short, lateral and above the middle of the body. 

In ponds and marshes, Florida and Alabama. Spring to fall. 



ALISMACEAE 



45 



12. Sagittaria papillosa Buch. Monoecious. Leaf-blades linear or linear-lanceo- 
late, 10-15 cm. long, acute, as long as the petioles or shorter : scapes 3-5 dm. tall: whorls 
of the inflorescence 3-10, the lower remote: pedicels of pistillate flowers 1-1.5 cm. long: 
bracts ovate, 3-4 mm. long, densely granular-papillose, united to about the middle : sepals 
ovate, roughened like the bracts : corollas »2-3 cm. broad : filaments not dilated, glabrous : 
mature fruiting heads subglobose, 6-10 mm. in diameter : achenes cuneate, 1.5 mm. long ; 
beak lateral and slightly above the middle of the body. 

In shallow ponds, Louisiana and Texas. Spring to fall, 

13. Sagittaria ambfgua J. G. Smith. Monoecious. Leaves erect ; blades lanceo- 
late, 12-50 cm. long, 5-nerved, shorter than the petioles: scapes 3-6 dm. tall, as long as 
the leaves or surpassing them : w^horls niunerous, commonly 8-15 : pedicels mostly ascend- 
ing, those of the pistillate heads longer than those of staminate ; bracts lanceolate, 10-15 
mm. long, united at the bases : filaments not dilated, glabrous : achenes oblong, slightly 
curved, 2 mm. long, narrowly Avinged, prolonged into short horizontal beaks at the top. 

In ponds, Kansas and Oklahoma. Summer. 

"""" 14. Sagittaria lancif olia L. Monoecious. Leaves 4-9 dm. tall ; blades leathery, 

broadly linear to elliptic, 3-6 dm. long, acute, commonly shorter than the petioles : scapes 
6-20 dm. tall, usually branched : whorls of the inflorescence numerous : pedicels of the 

{)istillate heads ascending, often shorter than those of the staminate : bracts ovate or ovate- 
anceolate, 1-2.5 cm. long, acute or acuminate: sepals obtuse: corollas 4-5 cm. broad; 
petals obovate : filaments not dilated, pubescent : mature fruiting heads fully 1 cm. in diam- 
eter : achenes cuneate or obovate, 2-3 mm. long, winged ; beak short, ascending. 
In marshes, Delaware to Florida, Texas and tropical America. Spring and summer, 

15. Sagittaria rigida Pursh. Monoecious. Leaf-blades 5-20 cm. long, linear, lance- 
olate, elliptic or broadly ovate, 7-9-nerved, acute or cordate at the base, sometimes with 
1 or 2 spreading or recurved basal lobes : scapes 1-8 dm. long, commonly shorter than the 
leaves, usually bent and sometimes branched at the lower whorl of the inflorescence : pedi- 
cels of the pistillate heads (1 or 2 lower whorls) barely 1 cm. long: bracts ovate, obtuse, 
4-8 mm. long, united at the base : mature fruiting heads 8-15 mm. in diameter, bristly by 
the protruding beaks of the achenes : achenes cuneate, 3-4 mm. long, winged ; beak stout, 
ascending. 

In swamps or running water, Quebec to Minnesota, New Jersey, Tennessee and Nebraska. Sum- 
mer and fall. 

16. Sagittaria longiloba Engelm. Monoecious, glabrous. Leaf-blades 10-18 cm. 
long ; terminal lobe linear to lanceolate ; basal lobes linear or linear-lanceolate, twice or 
thrice as long as the terminal one, long-acuminate : scapes 3-15 dm. tall, rarely branched : 
whorls of the inflorescence 4-8, remote, 1-3 lower very fertile : pedicels slender, 15-35 mm. 
long, spreading : bracts lanceolate, 6-8 mm. long, acuminate : filaments not dilated, gla- 
brous : mature fruiting heads 10-15 mm. in diameter : achenes cuneate, 1 mm. long ; wings 
somewhat undulate ; beak very short, lateral. 

On margins of shallow ponds, Nebraska to Colorado, Texas and Mexico. Summer and fall. 

17. Sagittaria longirdstra (Micheli) J. G. Smith. Monoecious, glabrous. Leaf- 
blades rather ample, 10-25 cm. long ; terminal lobe broadly ovate, abruptly pointed ; basal 
lobes ovate or oblong-lanceolate, acute, about i as long as the blade : scapes 4-8 dm. tall, 
sharply 6-angled : whorls of the inflorescence few, 1 or 2 lower ones usually pistillate : 
bracts triangular, 15-30 mm. long, acuminate : pedicels of the lower whorls 5-10 mm. 
long, ascending: mature fruiting heads spheroidal, 12-18 mm. in diameter: achenes 
obovate, 4 mm. long, the crest undulate ; beak about i as long as the body, curved ; facial 
wings prominent. 

On margins of ponds, New Jersey and Pennsylvania to Tennessee. Summer. 

18. Sagittaria vlsc6sa C. Mohr. Monoecious. Leaf -blades broadly ovate, 2-3.5 dm, 
long, rounded to the apiculate apex ; basal lobes ovate, acute or acuminate, shorter than 
the middle lobe : scapes 5-8 dm. tall, overtopping the leaves : pedicels in 8-10 whorls, of 
nearly equal length throughout: bracts leathery, ovate-oblong, obtuse, papillose, rugose 
and viscid : sepals leathery, ovate-lanceolate, roughened and viscid like the bracts : corol- 
las white, fully 1 cm. broad : filaments not dilated, pubescent : achenes not seen. 

In muddy plases and marshes, southern Alabama. Spring and summer. 

19. Sagittaria austr^lis (J. G. Smith) Small. Monoecious, slender. Leaf-blades 
oval or suborbicular, 8-10 cm. long, abruptly pointed at the apex, ciliate ; basal lobes 
ovate, barely J as long as the blade, obtuse : scapes 4-5 dm. tall, pubescent about the 
nodes in the inflorescence, angled, overtopping the leaves : whorls of the inflorescence 4-6, 
remote : .bracts lanceolate or ovate-lanceolate : pedicels of lower whorls 10-13 mm. long : 
achenes obovate, 3-3.5 mm. long ; crest undulate ; beak curved over the top of the crest, ^ 



46 



ELODEACEAE 



as long as the body ; facial wings prominent, 1 on each side. \_S. tongirostra austmlis J. 
G. Smith.] 

In low grounds, Alabama. Summer. 

20. Sagittaria Engelmannikna J. G. Smith. Slender, monoecious, glabrous. Leaf- 
blades narrow, 8-20 cm. long, shorter than the petioles ; lobes linear, 1-5 mm. broad, the 
terminal and basal about equal in length : scapes about as tall as the leaves, 2-6 dm. long : 



whorls of inflorescence 5-6, remote: bracts lanceolate, 8-12 mm. long; pedicels ascend- 
ing, those of staminate flowers often longer than those of the pistillate : sepals ovate, 6-7 
mm. long, acute : filaments not dilated, glabrous : mature fruiting heads subglobose, 12-14 
mm. in diameter : achenes obovate, 4 mm. long ; beak erect, ^-J as long as the body ; facial 

wings 1-3, 

In shallow water, Massachusetts to Florida. Summer. 

21. Sagittaria latif olia AYilld. Monoecious or dioecious. Leaf-blades ample, some- 
times broader than long, 15-40 cm. long, glabrous and rarely pubescent ; basal lobes ovate 
or lanceolate, acute or acuminate : scape 3-6 dm. long, angled : bracts J -5 cm. long, gla- 
brous, acute or acuminate : whorls of the inflorescence mostly distant: pedicels variable, 
those bearing pistillate heads 2-5 cm. long, or longer : filaments not dilated, glabrous : 
mature fruiting heads subglobose, 1.5-3 cm. in diameter : achenes obovate, about 3 mm. 
long, erect, undulate ; beak ascending or recurved. 

In swamps and shallow water, New Brunswick to British Columbia, Florida and Louisiana. Sum- 
mer and fall. 

r 

22. Sagittaria pub^scens Muhl. Monoecious or dioecious, puberulent or hirsute. 
Leaf-blades oblong or broadly ovate, 8-25 cm. long, usually abruptly pointed ; basal lobes 
ovate to lanceolate, about ^ as long as the blade or longer : scapes 3-6 dm. tall : whorls of 
the inflorescence remote : pedicels variable in length, surpassing the bracts : bracts ovate 
or suborbicular, obtuse, 7-10 mm. long: mature fruiting heads 8-15 mm. in diameter: 
achenes somewhat anvil-shaped or resembling the head of a bird, 2-3 mm. long ; beak 
horizontal or somewhat declined. 

In meadows or marshes, Ontario to Florida and Alabama. Summer and fall. 

23. Sagittaria Montevid^nsis Cham. & Schlecht. Monoecious, robust. Leaf -blades 
sagittate, 1-5 dm. long, often as broad, glabrous above, sparingly scabrous on the nerves 
beneath ; basal lobes acute or acuminate, more or less divergent, middle lobe acute : scapes 
sometimes 6-8 cm. thick at the base, usually simple : whorls of the inflorescence several or 
numerous, 2-4 of the lower ones pistillate : bracts lanceolate, acuminate, united below : 
pedicels of staminate flowers slender, 2-3 cm, long, surpassing those of pistillate flowers : 
sepals 10-15 mm. long, obtuse : petals white, obovate : filaments not dilated, glandular- 
pubescent, longer than the anthers : mature fruiting heads 1.5-3 cm. in diameter : achenes 
2-3 mm. long, rhomboid-obovate, winged ; beak slender, oblique ; faces flat. 

In swamps, North Carolina to Alabama and California, naturalized from South America. Spring 
and fall. 



Order 4. HYDROCHARITALES. 

Floating or more or less emersed herbs, perennial by rootstocks or stolons. 
Leaves usually with dilated blades. Flowers monoecious or dioecious, arising 
from spathes. Perianth of 2 dissimilar series, or the corolla rarely wanting. 
Androecium of 3-12 stamens. Gynoecium of 3-15 united carpels. Ovary in- 
ferior, with several parietal placentae or several -eel led. Endosperm wanting. 

Ovary 1-celIed, with 3. or rarely 2, 4 or 5 parietal placentae : stigmas usually 3. 

Fam. 1. Elodeaceae. 
Ovary 6-9-celled : stigmas fv-9. Fam. 2. Hydrocharitaceae. 

Family 1. ELODEACEAE bumort. Tape-grass Family. 

Floating or submerged sometimes acaulescent herbs, perennial by root- 
stocks or stolons. Leaves clustered or remote : blades short and broad or much 
elongated and ribbon-like. Flowers monoecious or dioecious, arising from a 
spathe or 1-3 bracts. Perianth regular, of 3 sepals and 3 petals, or the latter 
wanting, all more or less petaloid. Androecium of 3-12 stamens. Filaments 
distinct or monadelphous. Anthers 2-celled. Gynoecium a single pistil. Ovary 
inferior, l-celled with 3 or rarely 2-5 parietal placentae. Ovules mostly num- 
erous, orthotropous or anatropous. Fruit usually indehiscent, often becoming 



HYDROCHARITACEAE 47 



submerged and maturiug under water. Seeds with a straight embryo, without 
endosperm, 

Staminate flowers with 1-3 stamens. 

Spathes of pistillate flowers sessile or nearly so. of 2-3 distinct bracts. 1. Halophila. 

Spathes of pistillate flowers very long peduncled, of several more or less united 
bracts. 
Staminate flowers with 9 stamens. 



2. Vallisneria. 

3. Philotria. 



1. HALOPHILA Thouars. 



Marine herbs, with creeping rootstocks. Leaves opposite or whorled at the nodes, 
accompanied by stipule-like scales. Flowers dioecious, solitary in spathes, 2 or 3 distinct 
bracts arising between the leaves. Staminate flowers pedicelled : perianth of 3 rather 
herbaceous sepals. Stamens 3 : anthers nearly sessile, extrorse. Pistillate flowers sessile 



in the spathes : perianth of 3 minute sepals. Ovary 1-celled, with 3 parietal placentae, 
long-beaked. Style 3-parted : branches filiform. Fruit included in the spathe. Seeds 
numerous. Embryo with spirally bent cotyledons. 

1. Halophila Engelmdnnii Aschers, Floating, glabrous. Rootstocks branched, 
with many nodes : stems 10 cm. long, or shorter, commonly erect : leaves mainly whorled 
at the ends of the stem or its branches ; blades linear, oblong or oblanceolate, 1-3 cm. 
long, obtuse or acutish, sharply serrulate, 3-nerved, sessile : flowers and fruit not known. 

In coves and creeks, peninsular Florida. Spring to winter. 



2. VALLISNERIA L. 

Acaulescent submerged herbs, very delicate. Leaves basal : blades several-nerved, 
ribbon-like. Flowers dioecious. Staminate minute, numerous, crowded on a spadix 
enclosed in a spathe of 3 segments. Perianth of 3 sepals. Stamens 2 or 1-3. Pistillate 
flowers solitary at the ends of elongated cord-like spiral scapes, subtended by a tubular 
2-cleft spathe: petals 3, larger than the 3 green sepals. Ovary 1-celled, inferior, with 3 
parietal placentae: stigmas 3, each 2-lobed. Fruit elongated, leathery, indehiscent. 

1. Vallisneria spiralis L. Stoloniferous, flaccid, glabrous : leaf-blades narrowly 
linear, 1-18 dm. long, entire or serrate below the apex : flowers inconspicuous ; staminate 
basal, detached at maturity, floating and expanding on the surface ; pistillate floating, 
attached to the base of plant by elongated filiform scapes, which after fertilization coil 
spirally and submerge the flower : spathes cylindric, 1-2 cm. long, subtending one flower, 
membranous : fruit cylindric, 3-15 cm. long. 

In ponds or flowing water, New Brunswick to Minnesota, Florida and Texas. Summer and fall. 
Eel-grass, Tape-grass. 

3. PHILOTRIA Eaf. 

Caulescent submerged herbs, with slender rootstocks and branching stems. Leaves 
numerous, opposite or whorled : blades 1-nerved, Flowers polygamous or dioecious, from 
a sessile 2-cleft spathe. Sepals 3. Petals 3, thin. Staminate flowers minute, with 9 sta- 
mens. Fertile flowers pistillate or perfect : stamens 3-6, sometimes sterile. Ovary 



1-celled, with 3 parietal placentae. Stigmas apparently se&sile, 2-lobed. Ovules few. 
Fruit leathery, inhehiscent. ^Ehdea Michx., not Elodes Adans.] Water-wked. 

Leaf-blades oblong, elliptic or ovate-oblong : calyx over 2.5 mm. broad. 1. P. Canadcnsia. 

Leaf-blades narrowly linear or narrowlv linear-lanceolate: calyx less than 2.5 mm, 

broad. ' 2. P. minor, 

1. Philotria Canadensis (Michx.) Britton. Aquatic, flaccid. Stems variable in 
length, 1-12 dm, long, forking : leaves opposite or in whorls of 3 or 4 above the base ; 
blades oblong, elliptic or ovate-oblong, 4-15 mm. long, entire or serrulate ; whorls often 
approximate : flowers axillary ; staminate submerged, breaking ofi'at maturity and floating 
on the surface they discharge the pollen near the pistillate flowers, these floating, attached 
to the plant by the elongated stalk, which varies from 3-30 cm. in length : spathes 10-18 
mm. long. [Elodea Canadensis Michx.] 

In ponds and slow-flowing water, nearly throughout North America. Spring to fall. 

3. Philotria minor (Engelm.) Small. Similar to P. Canadensis in habit, but more 
slender, with more branched stems and less densely crowded leaves. Leaf-blades narrowly 
linear or narrowly linear-lanceolate : pedicels hair-like : calyx 1.5-2 ram. broad. 

In Donds and strpams Minnpsnta to Tennessee. Missouri and Arkansas. Summer. 



48 



POACEAE 



Family 2. HYDROCHARITACEAE Aschers. Frog's-bit Family. 

Aquatic or mud-inhabiting herbs. Leaves clustered, usually with well de- 
veloped blades, Flow^ers monoecious or dioecious, arising from spathes of distinct 
or united bracts. Perianth regular, superior, of 3 sepals and 3 i)etals. Androe- 
cium of 6-12 stamens. Filaments distinct or partially united. Gynoecium of 
6-15 united carpels. Ovary inferior, usually 6-9-celled. Styles as many as the 
cavities of the ovary. Ovules numerous. Fruit usually indehiscent. 

Leaf not differentiated into blade and petiole: flowers dioecious: stamens distinct: anthers nearly 

sessile. 1. Thalassia. 

Leaf differentiated into blade and petiole : flowers monoecious : stamens with united 

filaments. 2. LiMXOBirjr. 

1. THALASSIA Banks. 

Marine herbs, with elongated rootstocks. Leaves several at a joint, sheathing at the base : 
blades linear, elongated. Scape arising from the cluster of leaves. Flowers dioecious, solitary 
in narrow spathes of two bracts : these united into a tube at the base. Staminate flowers long- 
pedicelled : perianth of 3 petaloid sepals : stamens 6 : filaments very short : anthers open- 
ing laterally. Pistillate flow^er nearly sessile in the spathe, caducous : ovary 6-9-celled, 
beaked. Fruit stalked, rugose or nearly echinate, opening by many valves. Seeds numerous. 

1. Thalassia testudinum Koenig & Sims. Submersed, glabrous. Rootstocks creep- 
ing, elongated : stems short, arising from the nodes of the rootstock : leaves 2-5, sheathing 
the stem; blades linear, strap-like, 0.5-3 dm. long, obtuse, withering-persistent: scapes 
solitary, central : fruit globose or oval, echinate-pubescent, slightly pointed. 

In shaUow water, along the coast of peninsular Florida. Also in the West Indies. 

2. LIMNOBIUM L. C. Kich. 
Aquatic herbs usually floating and producing pendent roots and stolons. Leaves 
clustered : petioles elongated : blades broad, several-nerved. Flowers monoecious, from 
spathes of 2 membranous bracts. Perianth white : sepals 3 : petals 3, narrower than the 
sepals. Staminate flowers 2-4 in a spathe, usually with 6-12 stamens : filaments united into 
a column, bearing the anthers at diflFerent heights. Pistillate flowers with 3-6 abortive 
stamens, a 6-9-celled ovary with several central placentae : stigmas as many as the cavities 
in the ovary, each 2-parted. Fruit a many-celled berry. 



1. Limnobimn Sp6ngia (Bosc) L. C. Kich. Acaulescent, stoloniferous. Leaves 
basal ; petioles erect or ascending, 5-25 cm. long : blades ovate to suborbicularor reniform, 
2-5 cm. broad, obtuse, entire, truncate or cordate at the base ; petioles tapering to the 
blade : flowers monoecious ; staminate on scapes 8-10 cm. long ; pistillate on shorter and 
stouter scapes, these recurving at maturity : berry nodding, oval, 1-1.5 cm. long. 

In shallow water or mud, Ontario to Illinois and Missouri, to Florida and Louisiana. Frog's-bit. 

Order 5. POALES. 

Mostly perennial caulescent or acaulescent plants, commonly known as 

GRASSES and sedges. Stems (culms) simple or branched, sometimes conspicu- 
ously jointed. Leaves alternate, mostly sheathing at the base : blades usually 
narrow and elongated, entire or nearly so. Flowers variously disposed in a 
simple or compound inflorescence, perfect, or rarely monoecious or dioecious, 
incomplete, inconspicuous, in the axils of chaffy bracts or scales (glumes). 
Fruit a caryopis (grain) or an achene. 

Leaves 2-ranked. their sheaths with ununited margins : stems mostly hollow : fruit a grain (car>'opsis). 

Fam. 1. PoACEAE. 
Leaves 3-ranked. their sheaths with united margins : stems solid : fruitan achene. Fam, 2. Cyperaceae. 

Family 1. POACEAE K. Br.^ Grass Family. 

Annual or perennial herbs, rarely shrubs or trees, sometimes monoecious or 
dioecious, varying much in habit. Stems (culms) usually hollow, the nodes 
closed. Leaves alternate, 2-ranked, sheathing, the sheaths generally open to 
the base on the side opposite to the blade ; a scarious or cartilaginous ring 

^Contributed by Mr. George V. Nash. 



POACEAE 



49 



(ligule), naked or sometimes hairy, rarely wanting, occurs at the sheath-orifice. 
Inflorescence of spikes, racemes, or panicles, composed of spikelets, these con- 
sisting of 2-many 2-ranked imbricated bracts (scales), usually the lower 2, and 
occasionally the succeeding 2-4 scales also empty, rarely all the scales flower- 
bearing. One or more of the upper scales, except sometimes the terminal one,, 
bearing an axillary flower surrounded by a bract-like organ (palet), which ia 
placed opposite to the scale and with its back to the axis (rachilla) of the 
spikeletj usually 2-nerved or 2-keeled and awnless, rarely 1-nerved or awned ;. 
the palet is sometimes present without the flower and vice versa ; the rachilla 
is often thickened and appears as a hard projection (callus) at the base of the 
scale. Flowers perfect, staminate, or pistillatCj subtended by 1-3 minute 
scales (lodicules). Stamens 1-6, rarely more, usually 3. Anthers 2 celled^ 
versatile. Ovary 1-celled, 1-ovuled. Styles 1-3, commonly 2, distinct or more 
or less united, rarely wanting. Stigmas hairy or plumose. Fruit a seed-like 
grain (caryopsis), sometimes nut-like. Endosperm starchy. [^Gramineae Juss.} 

f 

A. Spikelets faUing from the pedicel entire (see also nos. 58, 61, 62, 68 and 76 of section B), naked, or en- 
closed in bristles or a bur-like involucre, or immersed in the internodes of a readily disarticulating 
rachis, l-flo\vered, or if 2-fiowered the lower flower staminate ; no upper empty scales : rachilla not 
extending beyond the uppermost scale. 

Spikelets round or somewhat dorsally compressed ; empty scales manifest : hilum punctiform. 

Flowering scale and palet hyaline, thin, much more delicate in structure than the thick-mem- 
branous to coriaceous empty scales. 



Spikelets unisexual, the pistillate borne in the lower, the 
staminate in the upper, part of the same spike. 

Spikelets in pairs, one sessile, the other pedicellate, the 
former perfect, the latter sometimes perfect, more com- 
monly with a staminate flower, often empty or reduced 
to one or two scales, or occasionally wanting ; both 
spikelets pedicellate in nos. 2 and 6. 

Flowering scale, at least that of the perfect flower, similar in 
texture to the empty scales, or frequently thicker and 
firmer, never hyaline and thin. 

Flowering scale and palet membranous. 

Inflorescence spicate : spikelets deciduous singly or in 
groups, the first scale usually larger than the rest. 

Inflorescence paniculate : spikelets deciduous singly 
from the ultimate brancnes, the first scale usually 
smaller or narrower than the rest. 

Flowering scale and palet chartaceous, cartilaginous, or 
coriaceous, very different in color and appearance 
from the remaining scales. 

Spikelets much compressed laterally; empty scales none or rudi- 
mentary : hilum linear. 



Tribe I. MAYDEAE. 



Tribe II. ANDROPOGONEAE 



Tribe III. ZOYSIEAE. 



Tribe IV. TKISTEGINEAE. 



Tribe V. PANICEAE^ 



Tribe VI. ORYZEAE. 



B. Spikelets with the empty scales persistent, the rachilla hence articulated above them (below them 
m nos. 58, 61, 62, 68 and 76 and the spikelet falling entire), 1-many-flowered ; frequently the upper 
scales are empty : rachilla often produced beyond the uppermost scale. 

Stems herbaceous, hence annual : leaf-blade sessile, not articulated with the sheath. 

Spikelets borne in open or spike-like panicles or racemes, usually upon distinct and often long, 
pedicels. 



Spikelets 1-flowered, 

Empty scales 4 : palet 1-nerved, 

Empty scales 2 (rarely 1) : palet 2-nerved. 

Spikelets 2-many-flowered. 

Flowering scales usually shorter than the empty ones, 
the awn dorsal and'usually bent. 

Flowering scales usually longer than the empty ones, the 
awn terminal and straight, rarely dorsal, sometimes 
wanting. 

Spikelets in two rows : 

On one side of the continuous axis, forming one-sided spikes, 
or racemes. 

On opposite sides of an axis, which is often articulated, 
forming equilateral spikes. 

'ms, at least near the base, woodv, hence perennial : leaf-blade 
with a petiole-like base which is articulated with the sheath. 



Tribe VII. PHALARIDEAE; 
Pribe VIII. AGROSTIDEAE. 



Tribe IX. AVEXEAE. 



Tribe XI. FESTUCEAE. 



Tribe X. CHLORIDEAE. 
Tribe XII. HORDEAE. 
Tribe XIII. BAMBUSEAE. 



Tribe I. 



DEAE 



Fertile spikelets imbedded in the internodes of the thick rachis. 



1. Tripsacum. 



4 



50 



POACEAE 



Tribe II. ANDROrOGONEAE. 

A. Internodes of the rachis not thickened nor excavated for the reception of 

the spikelets. 
Spikelets alike, perfect. 

Axis of the racemes continuous, not articulated. 

Axis of the racemes articulated. 
Spikelets not alike : ^ ,. „ . 

All pedicellate, the long-pedicellate one perfect, the short-pedicellate one 

staminate. 
Sessile and pedicellate, the former perfect, the latter empty, stammate 

or wanting. 
First empty scale of the sessile spikelet balsam -bearing. 
First empty scale of the spikelet not balsam-bearing. 

a. Sessile spikelets alike throughout the inflorescence. 
Kacemes singly disposed : apex of the rachis-internodes a trans- 
lucent cup-shaped, entire or irregularly toothed, appendage. 

Racemes disposed in pairs or more : apex of the rachis-inter- 
nodes not appendaged. 
Rachis-internodes and pedicels sulcate, the median portion 

translucent, the margins thickened. 
Rachis-internodes and pedicels not sulcate. 
Some or all of the racemes sessile. 
All of the racemes more or less pedunculate. 
Sessile spikelets dorsally compressed. 
Pedicellate spikelets wanting. 

Pedicellate spikelets present and usually staminate. 
Sessile spikelets rounded or laterally compressed. 
Racemes with many internodes : awns none. 
Racemes with usually but one internode : awns long. 

b. Lower spikelets differing from the others. 

B. Internodes of the rachis much thickened and excavated to receive the 

spikelets. 
First scale of the spikelet flat or convex. 
First scale of the spikelet globose. 

Tribe III. ZOYSIEAE. 
Second empty scale naked. 
Second empty scale with hooked spines on the back. 



2. iMrEUATA. 

3. EniAXTHVS. 



6. Trachvpogon 



7. ElIONT'RUS. 



8. SCHIZACHVRIUM. 



10. Amphilopsis. 
9. Andropogon. 



32. sokghastrum. 
11. Sorghum. 

13. Vetiveria. 
11. Raphis. 

15. IlETEROrOGON. 



4. Manisuris. 

5. llACKELOCHIX)A. 



16. HiLARIA 

17. Nazia. 



Tribe IV. TRISTEGINEAE. 
Inflorescence a panicle, the spikelets long-awned. 

Tribe V. PANICEAE. 
A. Spikelets all perfect. 

a. Spikelets not sunken in the rachis. 
1. Spikelets naked, not involucrate. 
Empty scale 1. 
Empty scales more than 1. 
Empty scales 2. 

Lower empty scale with a thickened ring-like callus. 
Lower empty scale unappendaged. 

Spikelets in one-sided racemes or spikes. 

Flowering scale with its opening turned from the rachis. 
Spikelets ovate to orbicular, usually obtuse, rarely acute. 
Spikelets lanceolate, acute to acuminate. 
Flowering scale with its opening turned toward the rachis. 
Spikelets in panicles ; 
Fertile. 

Sterile: fertile spikelets on short subterranean branches. 
Empty scales 3. 

Palet of the third scale not enlarged. 

Second empty scale not saccate at the base. 

Spikelets acute to obtuse, their empty scales not markedly 
exceeding the flowering ones, 
Spikelets sessile or nearly so, singly disposed : flowering 

scale Avith the opening toward the rachis. 
Spikelets more or less distinctly pedicellate, usually in 
pairs or more; flowering scale with the opening 
turned from the rachis. 
Empty scales not awned. 

Spikelets in very slender one-sided racemes which 

are usually whorled or approximate. 
Spikelets in panicles or panicled racemes, the lat- 
ter never whorled, commonly distant. 
Spikelets lanceolate, acuminate, long-hairy. 
Spikelets orbicular or lanceolate, if the latter 
then glabrous. 
Spikelets in pairs in one-sided racemes: first 
scale of the short-pedicelled spikelet 
turned to one side and often much 
longer than the corresponding scale in 
the other spikelet. 
Spikelets not in one-sided racemes, or if thus 
arranged, the first scale of the spikelets 
central. 



18. LiMNODEA. 



19. Reimaria. 



25. Eriochloa 



20. Paspalum. 
27. Synthertsma. 

22. Anastrophus. 

23. Anthaenantia. 

24. Amphicakpok. 



26. Brachiaria. 



27. Syntherisjia 



28. Trichachne. 



21. Dimorphostachys 



31. Panicum. 



POACEAE 



51 



B. 



Empty scales awned or awn-pointed. 

Stems creeping : leaf-blades short and broad : ra- 
cemes or clusters usually of few spikelets. 
Stems erect : leaf-blades long and narrow : ra- 
cemes usually of many spikelets. 
Spikelets and their empty' scales long-acuminate, the lat- 
ter not varying much in length and more than twice 
as long as the fourth scale. 
Second empty scale much enlarged, many-nerved, saccate at 
the base. 
Palet of the third scale much enlarged when mature, forcing 
open the spikelet. 
2. Spikelets involucrate. 

Involucre of numerous bristles. 

Bristles persistent : spikelets deciduous. 
Bristles not plumose. 
Bristles plumose. 
Bristles deciduous Avith the spikelets. 
Bristles rigid, thickened at the base. 
Bristles delicate, not thickened at the base, plumose. 
Involucre of two spine-bearing valves. 
b. Spikelets sunken in one side of the flat rachis. 

Spikelets monoecious: leaf-blades with a petiole-like base at the junction 
with the sheath. 



30. Oplismenus. 
29. echinochloa 



32. Phanopyuum 

33. Sacciolepis. 

34. Steinchisma. 



35. Chaetoculoa. 

39. Peniciixakia. 

37. Cencuroi*si8. 

38. Pennisetum. 

36. Cenchkus. 

40. Stenotaphrum. 

41. Olyka. 



Tribe VI. ORYZEAE. 

Spikelets monoecious. 

Inflorescence of short terminal and axillary spikes. 
Inflorescence paniculate. 

Spikelets in pairs, the larger one sessile and pistillate, the other small 

and staminate, pedicellate. 
Spikelets not in pairs. 

Spikelets linear. 
Spikelets ovate or elliptic. 

Pistillate and stammate spikelets in different panicles. 
Pistillate and staminate spikelets in the same panicle. 
Spikelets perfect. 

Empty scales present, manifest. 

Empty scales wanting, or rarely present as minute rudiments. 



42. HYDROCHX.OA. 



43. Pharus. 

46. ZlZANIA. 

44. LuzioLA. 

45. ZlZANlOPSIS. 

47. Oryza, 

48. Homalocenchrus 



Third and fourth scales empty : 

Awnless. 

Awned upon the back. 
Third and fourth scales enclosing 



Tribe VIJ. PHALARIDEAE, 



staminate flowers. 



49. Phalaris. 

50. Anthoxanthum 

51. Savastana. 



A 



B 



Tribe VIII. AGROSTIDEAE. 

Flowering scale indurated when mature and very closely embracing the 

grain, or at least firmer than the empty scales. 
Rachilla not extending beyond the palet. 
Flowering scale 3-awned. 
Flowering scale 1-awned. 
Awn untwisted : 

Stout : spikelets large. 
Slender ; spikelets small. 
Awn twisted. 
Rachilla extending beyond the palet. 

Flowering scale usually hyaline or membranous at maturity, at least more 
delicate than the empty ones : grain loosely enclosed. 

Inflorescence a spike. 

Rachilla of the spikelets articulated above the empty scales which are 

therefore persistent. . , 

Rachilla of the spikelets articulated below the empty scales, hence de- 
ciduous entire. 
Inflorescence an open or spike-like panicle. 

Grain not permanently enclosed in the flowering scale and palet: pen- 
carp opening readilv when mature. 
Grain permanently enclosed in the flowering scale ana palet: pencarp 

adherent. 

Spikelets readily falling off entire when mature. 
Spikelets with the empty scales at least persistent. 
Palet 1-nerved and 1-keeled : stamen 1. 
Palet 2-nerved and 2-keeled : stamens 3. 
Empty scales saccate at the base. 
Emptv scales not saccate at the base. 

Flowering scale with long hairs at the base. 
Flowering scale and palet thin-membranous. 
Flowering scale and palet chartaceous. 
• Flowering scale 5-nerved. 
Flowering scale 1-nerved. 
Flowering scales naked at the base. 

Inflorescence an elongated narrow panicle. _ 

Inflorescence an open, or short and spike-like panicle. 



52, Aristida. 



53. Ortachne. 

55. Muhlenbergia. 

54. Stipa. 

56. Brachyelytrum 



57. Phleum. 

58. Alopecurus 



59. Sporobolus, 



61. POLYPOGOX. 

62. Cinna. 

64, Gastridium 



65. CALAMAGKOrtTlS. 

Q'>. Ammopuila. 

67. CAi-A.MuVJJ,FA. 

60. Epicampes. 
63. Agrostis. 



52 



POACEAE 



Tribe IX. AYENEAE. 

Spikelets readily deciduous as a whole. . , a -^ 

Spikelets with the empty scales persistent, the flowering scales deciduous. 

Spikelets 2-flowerea : rachilla not prolonged. 

Spikelets 2-niany-flowered : rachilla extending beyond the upper flower. 

Flowering scale awned below the teeth. 

Flowers all perfect. ., , , ^ . 

Grain free, unfurrowed : spikelets less than 1 cm. long. 

Flowering scales erose-toothed or shortly 2-lobed at the apex. 
Flowering scales cleft or 2-toothed, the teeth extending into 

Grain furrowed, adherent to the scale : spikelets exceeding 1 cm. 

in length. . . , .* 

Flowers different, the upper perfect, the lower stammate and with its 

scale strongly awned. . 

Flowering scales awned between their usually awned teeth. 

Tribe X. CHLORIDEAE. 

A. Spikelets with perfect flowers. 
Spikelets deciduous as a whole. 
Spikelets with at least the empty scales persistent. 
Spikelets with one perfect flower. 
No scales above the flowering scale. 

Spikes 2-6, digitate. 

Spikes numerous, arranged along a common axis. 

1-several scales above the flower. 

Empty scales 4. 

Empty scales 2. 

Spikes in whorls or closely approximate. 

Flowering scales with a single awn or awnless. 

Second empty scale acute : awn of flowering scales usually 

long. 

Second empty scale truncate or 2-toothed : flowering scales 

awnless or awn-pointed. 

Flowering scales with three awns. 

Spikes scattered. 

Spikelets scattered or distant. 

Spikelets crowded. 

Spikes generally 4 or less, rarely as many as 8, long : spike- 
lets numerous, exceeding 12. 
Spikes often numerous, short : spikelets few, less than 12. 
Rachis of the spikes with manifest internodes. 

Spikelets broad, crowded ; internodes of the rachis 
short : rachilla terminated by a 3-awned scale, 
or sometimes reduced to 3 weak awns. 
Spikelets very narrow, scattered : internodes of the 
rachis at least ^ as long as the spikelets: ra- 
chilla terminated by 3 stout awns. 
Rachis with the internodes so short that the spikelets 
appear clustered. 
Spikelets with 2-3 perfect flowers. 

Spikes commonly digitate ; spikelets crowded. 
Spikes with terminal spikelets. 

Spikes with the rachis extending beyond the spikelets in a manifest 
point. 

Spikes distant : spikelets alternate. 

Spikelets small, numerous and crowded : scales thin. 
Spikelets large, few and distant : scales firm and thick. 
B. Spikelets dioecious, those of the two sexes very dissimilar. 



68. Ho LOUS, 

69. AiKA. 



70. Deschampsia, 

71. Trisetum. 

72. AVENA. 

73. Arrhenatherum 

74. Danthonia. 



76. Spartina. 



75. Capriola. 

82. schedonnardus 

77. Campulosus. 



78. Chloris. 

79. EUSTACHYS. 

80. Trichloris. 

81. Gymnopogon 



83. BOUTELOITA. 



84. ATHEROPOGON. 



85. Triathera 

86. POLYODON. 



87. Eleusine. 

88. Dactyloctenium 

89. Leptochloa. 

90. Acamptoclados. 

91. bulbilis. 



.^ 



Tribe XI. FESTUCEAE. 

Flowering scales many-cleft into awn like divisions. 
Flowering scales entire, or at most 2-lobed. 

Hairs on the rachilla or flowering scale very long and enclosing the latter : 
tall reed-like grasses. 
Flowering scales hairy : rachilla glabrous. 
Flowering scales glabrous : rachilla hairy. 
Hairs, if any, on the rachilla or flowering scales shorter than the scale: 
grasses of lower stature. 

Stigmas barbellate, on elongated styles. 

Spikelets dioecious, single, concealed in the heath-like leaves. 

Spikelets perfect, commonly in 3*8, in the axils of stiff spinescent leaves. 
Stigmas plumose, sessile or on a short style. 

Flowering scale 1-3-nerved, or rarely with faint additional interme- 
diate nerves. 

Flowering scales membranous : seed not beaked nor exserted from 
the scale. 
Lateral nerves of the flowering scale pilose. 

Internodes of the rachilla long, the deeply 2-lobed flowering 
scales attached by a long pointed callus. 

Internodes of the rachilla and the blunt callus of the flower- 
ing scale short. 

Inflorescence simple or compound, contracted or open, the 
spikelets on pedicels of varying length. 



92. Pappophorum 



95. Arundo. 

96. Phragmites. 



93. Monanthochloe 

91. MUNROA. 



99. Triplasis. 



POACEAE 



53 



Inflorescence a short congested raceme : leaf-blades 

with thick conspicuous cartilaginous margins. 98. Erioxeuron. 

Inflorescence a contracted or open panicle : leaf-blades 

not cartilaginous on the margins. 97. Tuidexs, 

Inflorescence composed of long branches along which the 
appressed spikelets are arranged on short pedicels, or 
sometimes only a one-sided raceme. 101. Diplachne. 

Lateral nerves of the flowering scale glabrous. 

Callus of the flowering scales copiously pubescent with long 
hairs. 
Panicle contracted : flowering scales broadly oval» rounded 

at the apex. 102. Rhomuulytrum. 

Panicle open and diffuse : flowering scales lanceolate and 

acute. 100. Redfieldia. 

Callus of the flowering scales glabrous. 
Second empty scale similar to the first. 

Rachilla of the spikelet continuous : palets often per- 
sistent. 103. EllAGROSTIS. 

Rachilla of the spikelet articulated. 

Spikelets very small and numerous, less than 3 mm. 

long, usually several-many-flowered. 103. Eragrostis. 

Spikelets large, about 6 mm. long, 2-3-flowered. 105. Koeleria, 

Second empty scale very dissimilar to the first, broad and 

rounded at the summit. 101. Eatonia. 

Flowering scale coriaceous in fruit : seed beaked and exsertcd from 

the scale. 107. Korycarpus. 

Flowering scales 5-many-nerv'ed. 

Spikelets with two or more of the upper scales empty, broad and 

enfolding each other. 106. Melica. 

Spikelets with the upper scales flower-bearing, or smaller and 
empty. 
Empty basal scales 3-6. 108. Unioi.a. 

Empty basal scales 2. 

Spikelets dioecious. 109. Distichijs. 

Spikelets perfect : 

Borne in fascicles which are arranged in a glomerate or in- 
terrupted panicle. 110. Dactylis. 
Borne in panicles or racemes, but not in fascicles. 
Stigmas inserted at or near the apex of the ovary. 

Flowering scales with the nerves parallel. 112. PANictJLARiA. 

Flowering scales with the lateral nerves converging 
above toward the midnerve. 
Flowering scales strongly keeled on the back, pu- 
bescent on some or all of the nerves : hilum 
punctiform. 111. Poa. 

Flowering scales rounded on the back, at least 

below : hilum linear. 113. Festuca, 

^ Stigmas plainly inserted below the apex of the ovary. 114. Bromus. 

Tribe XII. HORDEAE. 

"Spikelets singly arranged at the rachis nodes. 

Spikelets with the flowering scales with their backs to the rachis ; empty 

scale 1. 115. Lolium. 

Spikelets with the flowering scales with their sides to the rachis : empty 

scales 2. 116. Agropyron. 

Spikelets 2-6 at each rachis node : 

1-flowered. 117. Hordeum. 

2-man y-flowered . 

Empty scales usually as long as the flowering ones. 

Rachis of the spike articulated, its internodes readily separating at 

the joints: empty scales 2-many-parted or cleft. 118. Sitanion. 

Rachis of the spike continuous : empty scales entire. 119. Elymus. 

Empty scales wanting or minute. 120. Hystrix. 

Tribe XIII. BAMBUSEAE. 
Shrubs or trees with the leaf-blades usually articulated with the sheaths. 121. Arundinxria. 

1. TRfPSACUM L. 

Tall perennial monoecious grasses, witli stout rootstocks, usually broad flat leaf -blades 
and spicate inflorescence. Spikes articulated, elongated. Staininate spikelets 2-flowered, 
in pairs at each joint of the upper portion of the axis, of 4 scales, the outer 2 empty, 
coriaceous and shining, the inner 2 thinner, each enclosing a hyaline palet and a flower 
consisting of 3 stamens. Pistillate spikelets 1-flowered, in excavations in the lower inter- 
nodes of the rachis, the outer scale very hard, thick and shining, concealing the more deli- 
cate remaining scales, the fourth scale enclosing a flower with a slender style. Stigmas 2, 
exserted. Grain enclosed in the appressed outer scale and the internode. 

Spikes in pairs or more, rarely single, terminal and axillary: leaf-blades 1-2 cm. 

broad. f j ^ ^ ^ dactylaides. 

Spike single, terminal, none axillary : leaf-blades 8 mm. broad or less. 2. T. Floridanum. 



64 



POACEAE 



1. Tripsaciun dactyloides L. Glabrous, or on the summit of tlie sheaths and the 
upper surface of the leaves more or less hirsute. Stems 1-2.5 m. tall, from stout root- 
stocks ; blades 6 dm. long or less, 1-4 cm. wide : spikes terminating the stem and its 
branches, single, or at the summit of the stem in 2's-4's, 1-3 dm. long, the lower \-^ 
pistillate, the remainder staminate, the margins of the excavations in the pistillate portion 



ciliate, the sinus at the base with long hairs : pistillate spikelets 7-10 mm. long, orbicular- 
ovate : staminate spikelets 7-10 mm. long, 1.5-2 mm. broad, oblong, the outer 2 scales 
glabrous or puberulent. 

In swamps or along streams, Rhode Island to Kansas, Florida, Texas, and Mexico. Summer and 
fall. Gam A Grass. 

2. Tripsacum Floridanum Porter. Similar to the preceding species, but much more 
slender. Stems from stout rootstocks, 6-10 dm. tall : leaf-blades long and narrow, usually 
5-8 mm. wide : spikes rather slender, 1.5-2 dm. long, single, terminal, never axillary. 

In moist or wet places, peninsular Florida and the Keys to Texas. Spring and summer. 



2. IMPERATA Cyr. 

Perennial grasses, with long leaf-blades and long terminal cylindric dense and spike- 
like panicles. Spikelets 1-flowered, rarely 2-flowered, narrow, in pairs, unequally pedicel- 
late. Scales 4, thin, hyaline, awnless, the outer 2 empty, pilose, the third scale glabrous, 
empty or rarely enclosing a palet and staminate flower, the fourth scale glabrous, subtend- 
ing a perfect flower and its 2-nerved palet which is truncate and toothed at the apex. 
Stamens 1 or 2. Styles distinct. Stigmas plumose. 

1. Imperata 6rasili6nsis Trin. Stems tufted, 3-8 dm. tall, slender : leaf -sheaths 
smooth and glabrous ; blades 3 dm. long or less, 3-8 mm. wide, smooth beneath, hirsute 
above near the base: panicle 6-15 cm. long, 1.5-3 cm, broad, oblong, its branches 1.5-4 
cm. long, ascending : spikelets about 4 mm. long, the one about equalling, the other about 
twice as long as its pedicel, the outer 2 scales and the callus densely clothed with hairs, 
these, as well as those at the summit of the rachis intemodes, more than twice as long as 
the spikelets. 

In dry soil, southern peninsular Florida. Also in tropical America. Spring and summer. Bra- 
zilian Blady-grass. 

3. ERIANTHUS Michx. 

Tall perennial grasses, with frequently robust stems arising from thick rootstocks, and 
with flat leaf -blades and perfect flowers in open or contracted terminal panicles. Spikelets 
usually with a basal ring of long hairs, or rarely naked, in pairs at each joint of the artic- 
ulated and often hairy rachis. Scales 4, the outer 2 indurated, frequently hairy, the re- 
mainder hyaline, the fourth scale often 2-toothed at the apex, bearing an awn which i* 
straight, spiral, or more or less contorted ; palet small, hyaline. Stamens 3. Styles dis- 
tinct, elongated- Stigmas plumose. Plume Grass, Beard Grass. 

Spikelets with a basal ring of hairs at least }4 its length, the outer 2 scales long- 
pilose or becoming glabrous. 

Panicle pale, rarely tinged with purple, the basal hairs much exceeding the 
usually yellowish white spikelet. 
Exserted portion of the awn loosely coiled, the included part tightly spiral. 1. E, cHopeeiiroida. 
Exserted portion of the awn straight, the included portion rarely slightly 
twisted. 
Panicle dark, often tinged with purple, the basal hairs'from^shorter than to ex- 
ceeding the yellowish brown or dark brown spikelet. 
Exserted portion of the awn straight. 

Spikelets 6 mm. long or less, equalling or shorter than the basal hairs. 
Panicle dense and compact, its branches short and erect ; basal hairs 
about as long as the spikelet. 

Panicle loose and open, its branches long and ascending ; basal hairs 
much exceeding the spikelet. 
Internodes of the branches commonly about as long as the spikelets 

which are about % as long as the basal hairs. 4. E. saccharoides, 

Lower internodes of the elongated branches much exceeding the 

spikelets which are about % as long as the basal hairs. 5. E. laxns. 

Spikelets 8 mm. long or more, exceeding the basal hairs. 6. E. brevibarUs, 

Exserted portion of the awn contorted or loosely spiral. 

Spikelets 7.5 mm. long or less ; summit of the stem and panicle-axis gla- 
brous or sparingly appressed-hirsute. 7. E. contortus. 
Spikelets 8-9 mm. long ; summit of the stem and panicle-axis densely ajh 
pressed-hirsute. 

Spikelet naked at the base or with a few short hairs, the outer 2 scales strongly ap- 
pressed-hispid. 



2. E. Traeyi. 



3. E, compacius. 



8. E, SmaUii. 



9. E, strictus. 



rOACEAE 



55 



1. Erianthus alopecuroides ( L. ) EH. Stems 1.5-3 m. tall, tlie apex, the panicle-axis^ 
and often also the nodes, pubescent with lon^^ silky apj)ressed hairs. Leaf-sheaths gla- 
brous ; blades 1.5-7 dm. long, 5-25 mm. broad, hirsute above near tlie base : panicle 2-3- 
dm. long, 5-10 cm. broad, oblong, its branches erect-ascending, the larger 4-11 cm. long : 
spikelets rather crowded, about § as long as the basal hairs and ^ again as long as the inter- 
nodes ; 2 outer scales about 6 mm. long, pilose with hairs less than Ih times as long as the- 
scales ; fourth scale 2-toothed at^the apex, the tectli acuminate, the aVn 12-lG mm. long, 
tlie included portion a tightly spiral column, the remainder loosely coiled. 

In damp soil, Xorth Carolina, Kentucky and Missouri, to Georgia and Alabama. Fall.— A form. 
E. alopecuroides hirsutus Nash, differs from the species in having the sheutJis, at least the lower ones, and 
the lower surface of the leaf-blades appressed-hirsute. In similar situations, Florida. 

2. Crianthua Tracyi Nasli. Stems 2-4 m. tall, the summit and nodes togetlier with 
the panicle-axis and top of the otherwise glabrous sheaths appressed-pubescent witli long 
silky hairs. Leaf-sheaths shorter than the internodes ; blades 5 dm. long or more, 1.5-3 
cm. broad, very rough, pilose above at the base : panicle 3-5 dm. long, 8-12 cm. wide, ob- 
long, its pubescent branches erect-ascending, the larger 1-1.5 dm. long: spikelets crowded, 
less than ^ as long as the basal hairs and I again as long as tlie internodes ; 2 outer scales 
5-6 mm. long, pilose with hairs twice as long as the scale ; fourth scale entire or somewhat 
2-toothed at the apex, the awn 1.5-2 cm. long, straight or slightly flexuous. 

In moist open places, Florida and Mississippi. Fall. 

3. Erianthus compdctus Nash. Stems 1-2 m. tall, the summit and nodes together 
with the panicle-axis and top of the otherwise glabrous sheaths appressed-pubescent with 
long silky hairs. Leaf-sheaths shorter than the internodes ; blades 1.5-7 dm. long, 6-12 
mm. wide, rough on both surfaces, more or less appressed-hirsute beneath, also above near 
the base: panicle 1-2 dm. long, 4-6 cm, wide, oblong, its branches erect-ascending, the 
larger 3-5 cm. long : spikelets crowded, about equalling the basal hairs, and usually over 
twice as long as the internodes ; 2 outer scales 5 -6 mm. long, pilose with long hairs ; fourth 
scale slightly if at all toothed at the apex, the awn straight or slightly flexuous, 1-2 cm. long. 

In swamps, New Jersey to North Carolina and Tennessee. Fall. 

4. jBrianthus saccharoides Michx. Stems 1.5-3 m. tall, the summit and nodes to- 
gether with the panicle-axis and top of the otherwise glabrous sheaths a])pressed-pubes- 
cent with long silky hairs. Leaf-sheaths shorter than the internodes ; blades 1.5-7 dm. long, 
6-25 mm. wide, usually rough and more or less hirsute on both surfaces :j)anicle 1.5-4 dm. 
long, 5-15 cm. wide, oblong, its branches ascending, the larger 7-15 cm. long : spikelets 
rather loosely disposed, about f as long as the basal hairs and a little exceeding the inter- 
nodes ; 2 outer scales ^^6 mm. long, pilose with long hairs ; fourth scale slightly if at all 
toothed at the apex, the awn straight or slightly flexuous, L5-2.5 cm. long. 

In moist soil, New Jersey to Florida and Louisiana, ' Summer and fall. 

5. Iitianthiis Idzus Nash. Stems 2-3 m. tall, pubescent, especially at the nodes, 
with appressed hairs, those at the apex and on the panicle-axis long and copious. Leaf- 
sheaths, particularly the lower ones, densely hirsute, especially at the ends ; blades 2-6 
dm. long, 6-12 mm. wide, hirsute on both surfaces, the upper surface becoming glabrous : 
panicle 4-5 dm. long, 1 dm. wide or less, its elongated and ascending branches lax and 
flexuous, the larger 2-2.5 dm. long : spikelets loosely disposed, i as long as the basal hairs 
and much exceeded by the internodes, especially by the lower ones ; 2 outer scales 4-5 
mm. long, pilose with long hairs ; fourth scale entire or shortly 2-toothed at the apex, the 
awn straight or slightly flexuous, about 2 cm. long. 

In swamps, peninsular Florida. Fall. 

6. Brlanthus brevlbdrbis Michx. Stems 1-1.5 m. tall, the nodes pubescent with 
readily deciduous hairs, the summit and panicle-axis glabrous. Ijeaf-sheaths rough, the 
summit appressed-hirsute ; blades 1.5-4 dm. long, 6-10 mm. wide, rough : panicle 2-3 
dm. long, about 3 cm. wide, its branches erect, the larger 2-7 cm. long : spikelets crowded, 
exceeding the basal hairs and a little less than twice as long as the internodes ; 2 outer 
scales 8-9 mm. long, sparingly pilose ; fourth scale usually entire at the apex, the awn 
straight, 1.5-2.5 cm. long. 

In moist soil, Delaware to North Carolina and Louisiana. Fall. 

7. Erianthus contdrtus Ell. Stems 1-2 in. tall, the nodes often pubescent with 
readily deciduous hairs, the summit and panicle-axis glabrous, or sparingly appressed- 
pubescent. Leaf-sheaths smooth or rough ; blades 1.5-8 dm. long, 5-20 mm. wide, 
smoothish or rough : panicle 1.5-3 dm. long, 3-5 cm. wide, its branches erect, the larger 
4-7 cm. long : spikelets crowded, exceeding the basal hairs and about I again as long as 
the internodes ; 2 outer scales 7-7.5 mm. long, at first more or less pilose with long hairs ; 



fourth scale 2-toothed at the apex, the awn 1.5-2 cm. long, the included portion often a 
little spiral at the base, the remainder loosely spiral. 
In pine woods, Delaware to Florida and Mississippi. Fall. 



^6 



POACEAE 



8. Erianthus Smdllii Xash. Stems 1.5-2.5 ra. tall, the nodes pubescent with readily 
deciduous hairs, the summit and tlie panicle-axis copiously appressed-i)ubescent with long 
silky hairs. Leaf-sheaths usually sparingly hirsute at tlieapex, otherwise glabrous ; blades 
1.5-7 dm. long, 6-20 mm. wide, rough on both surfaces : panicle 2-4 dm. long, 4-6 cm. 
wide, its branches erect, the larger 7-10 cm. long : spikelets crowded, about equalling the 
basal hairs and J again as long as the internodes ; 2 outer scales 8-9 mm. long, pilose with 
long hairs ; fourth scale 2-toothed at the apex, the teeth long and subulate, the awn 2-2.5 
cm. long, the included portion long and tightly spiral, the remainder loosely spiral. 

In low grounds, Tennessee to Georgia, Florida and Mississippi. Fall. 

9. Erianthus strictus Baldw. Stems 1-2 m. tall, the nodes usually pubescent with 
readily deciduous hairs, the summit and the panicle-axis glabrous. Leaf -sheaths glabrous ; 
Llades 2-7 dm. long, 5-10 mm. wide, rough on the margins but otherwise smooth : pan- 
icle 2-4 dm. long, 1-2 cm. wide, its branches appressed, the larger 5-8 cm. long : spikelets 
<;row^ded, about J again as long as the internodes, the basal hairs wanting or sparse and less 
than } as long as the spikelet ; 2 outer scales 8-10 ram. long, strongly appressed-hispid ; 
fourth scale entire or shortly 2-toothed at the apex, the awn 1.5-2 cm. long, straight. 

In moist soil, Tennessee to Florida and Texas. Fall. 

4. MANISURIS L. 

Perennial, often tall grasses, sometimes with rootstocks, narrow flat leaf-blades, and 
cylindric articulated terminal and axillary spikes. Spikelets in pairs at each joint, in ex- 
cavations in the rachis, one sessile and containing a perfect flower, the other pedicellate 
and either bearing a staminate flower, or empty. Scales of the sessile spikelet 4, the 
outermost thick and coriaceous, sometimes more or less rugose or pitted, concealing, to- 
gether with the pedicel of the other spikelet, the remaining scales and the excavation in 
the rachis ; second scale chartaceous, the third and fourth scales hyaline, the former empty 
or infolding a staminate flower, the latter enclosing a thinly hyaline palet and perfect 
flower. Scales of the pedicellate spikelet 4 or fewer. Stamens 3. Styles distinct. 
IRottboellia L. f.] Eat -tail Grass. 

Stems from horizontal rootstocks, round ; sheaths round, narrow. 1. M. cylindrica. 

Stems tufted, much flattened, at least below ; rootstocks wanting ; sheaths much com- 
pressed, broad, keeled. 
First scale of the sessile spikelet transversely wrinkled (rarely smooth). 

Wrinkles short, but little elevated, tubercle-like, sometimes entirely wanting. 2. M, tuberculosa. 
Wrinkles long, often extending completely across the scale, much elevated. 
Leaf-blades rather short and broad, especially those of the upper sheaths, 

6-10 mm. wide at the base : rachis of the racem.es glabrous. 3. M. ChapmaniL 

Leaf-blades elongated and narrow, even those of the upper sheaths, 6 mm. 

wide at the base or less : rachis of the racemes puberulent. 4. M, rugosa. 

First scale of the sessile spikelet pitted. 5. Jtf. tessellata, 

1. Maniatirls cylindrica (Michx. ) Kuntze. Stems from creeping rootstocks, round, 
3-10 dm. tall, slender : leaf-sheaths round, narrow ; blades 3 dm. long or less, 1-3 mm. 
wide : racemes finally exserted, 1-2 dm. long, straight or curved, the rachis barely if at all 
contracted at the nodes: sessile spikelet 4.5-5 mm. long, about equalling the internode, 
the first scale more or less pitted in longitudinal lines, or rarely unpitted, each pit often con- 
taining a subulate hair ; pedicellate spikelet reduced to 1 or 2 short scales, the pedicel 
linear, shorter than the sessile spikelet and curved around its margin. \_Itottboellia cylin- 
drica (Michx.) Chapm.] 

In sandy soil, Georgia and Florida to Texas ; also in Missouri and the Indian Territory. Summer^ 

2. Manisuris tuberculosa Nash. Stems tufted, much compressed, 8-12 dm. tall, 
stout : leaf-sheaths much flattened, broad, keeled ; blades 3 dm. long or less, 3-7 mm. 
wide : racemes finally exserted, 6-10 cm. long, straight, the rachis barely if at all contracted 
at the nodes : sessile spikelet about 4 mm. long, about equalling the internode, the first 
scale transversely wrinkled, or very rarely without wrinkles, the wrinkles short, tubercle- 
like, irregularly disposed ; pedicellate spikelet reduced to 1 or 2 short scales about J the 
length of the linear pedicel which is a little shorter than the sessile spikelet and curved 
around its margin. 

On lake shores, peninsular Florida. Summer. 



3. Manisuris Chapmdnii (Hack.) Nash. Stems tufted, 6-15 dm. tall, much com- 

{►re.->sed : leaf -sheaths much flattened, broad throughout ; blades usually less than 2.5 dm. 
ong, 6-10 mm. wide, those of the inflorescence generally very short and broad : racemes 
commonly 4-5 cm. long, occasionally longer, little compressed, exserted or a little included 
at the base, the rachis glabrous, the internodes and pedicels usually flat, not much de- 
pressed on the back : sessile spikelet 4-5 mm. long, usually exceeding the stout inter- 



POACEAE 



57 



node; pedicellate splkelet smaller and of 2 scales, or sometimes staminate and as long as 
the linear pedicel. 

In swampy places, Florida. Fail. 

4. Manisuris rugosa (Nutt. ) Kuntze. Stems tufted, much compressed, 7-12 dm. 
tall, stout: leaf-slieaths much flattened, broad, keeled ; blades 4 dm. long or less, 6 mm. 
wide or less : racemes exserted or somewhat included at the base, 5-8 cm. long, straight or 
a little curved, the rachis internodes usually much contracted at tlie base and i)uberulent : 
sessile spikelet 3.5-4,5 mm. long, about equalling or a little exceeding the internodes, the 
first scale strongly transversely wrinkled, the M'rinkles much elevated and often extending 
across the entire width of the scale, the longitudinal ridges usually rather })rominent, often 
2-toothed at the obtuse ixpex ; pedicellate spikelet of 2 scales, *i as long as the clavate 
puberulent pedicel or less. IBottboellia rmjosa Nutt. RoiihoelUa coirugata I>aldw.] 

In wet places, Delaware and Maryland to Florida and Texas. Summer and fall. 

5. Manisuria tessellata (Steud. ) Scribn. Stems tufted, much compressed, 8-12 dm. 
tall, stout : leaf-sheaths nuich flattened, broad, keeled ; blades 4 dm. long or less, 3-8 
mm. wide : racemes finally exserted, 6-12 cm. long, straight, the rachis barely if at all 
contracted at the nodes : sessile spikelet about 5 mm. long, a little exceeding the inter- 
node, the first scale deeply pitted, the pits quadrangular: pedicellate spikelet of 1 or 2 
scales, about ^ as long as the straight linear pedicel which is snorter than tlie sessile spike- 
let. [^Rottboellia corrur/ata Chapm., not Baldw.] 

In low pine lands, Alabama to Louisiana. Summer and fall, 

5. HACKELOCHLOA Kuntze. 

Annual grasses, with branching stems, flat leaf-blades and terminal and axillary short 
spikes which are sometimes partially included in the sheaths. Spikelets in pairs in excava- 
tions at the rachis-joints, one sessile, l-flowered, the other pedicellate, flowerless. Scales 
of the sessile spikelet 4, awnless, the outermost empty, firm, globose, pitted, covering the 
excavation in the rachis, the second small, concave, thin, somewhat rigid, the third empty, 
the fourth small, thin, hyaline, enclosing a perfect flower and sometimes also a minute 
palet. Stamens 3. Styles distinct. Stigmas plumose. l^Manisriris Sw\, not L.] 

1. Hackelochloa granularis (L. ) Kuntze. Stems tufted, 2-10 dm. tall, finally 
much branched: leaf-sheaths papillose-hirsute; blades 1.5 dm. long or less, 3-15 mm. 
wide, papillose-hirsute on both surfaces, ciliate on the margins : racemes 1-2 cm. long, the 
peduncles hirsute : sessile spikelet about 1 mm. in diameter ; pedicellate spikelet about 2 
mm. long, sterile, consisting of 2 scales. [Manisuris granularis Sw.j 

In cultivated and waste places, Georgia and Florida to Arizona. Also in all tropical regions. 
Summer and fall. Lizard-tail Grass. 

6. TRACHYPOGON Nees. 

Tall perennial grasses, w^ith long narrow leaf-blades and spike-like terminal racemes. 
Spikelets l-flowered, one almost sessile and staminate, or if perfect, sterile, the other ped- 
icellate and enclosing a perfect flower. Scales usually 4 ; the first scale rigid, awnless, en- 
closing the rest, the second somewhat resembling the first but smaller and thinner, the 
third scale very thin and hyaline ; fourth scale in the sessile spikelets very thinly hyaline, 
awnless, in the pedicellate spikelet very narrowly hyaline at the base, and produced into a 
very long contorted awm which is geniculate above. Palet minute or wanting. Stamens 
3. Styles distinct. Stigmas plumose. 

1. Trachypogon seciiadus (Presl) Nash. Stems tufted, 8-10 dm. tall, simple, the 
nodes barbed : leaf-blades erect, 1-3 dm. long, about 3 mm. wide, hirsute on the upper 
surface : racemes 1-2 dm. long, the rachis glabrous : short-pedicellate spikelet about 7 mm. 
long, the long-pedicellate one about 9 mm. in length, the hrst scale of both copiously pu- 
bescent with rather long ascending hairs, the awn of the latter 4-6 cm. long, twisted at 
the base and geniculate, pubescent below with long nearly erect hairs which become much 
shorter toward the summit. [Heteropogon secundus Presl.] 

In drj' soil, Texas to Arizona, south to Mexico. Summer and fall. 

7. ELIONURUS H. & B. 

Tall and branched, or low and tufted grasses, with often elongated leaves, and tenninal 
spikes. Spikelets in pairs in excavations at the rachis-nodes ; one sessile, l-flowered, or 



rarely 2-flowered ; the other pedicellate, sometimes enclosing a flower. Scales 4, awnless, 



58 



POACEAE 



the outermost one larger than tlie rest, meiubranous, exlialin^: a balsam-odor when fresh 
or when soaked in water, second scale sliorter, thinner, somewhat rigid, acute, the third 
scale empty, or rarely in the sessile spikelets infolding a staminate flower, the fourth scale 
very thinly hyaline, in the sessile spikelets enclosing a perfect flower, in the pedicellate 
spikelets either empty or enclosing a staminate flower ; palet minute or wanting. Stamens 
3. Styles distinct. Stigmas plumose. 

1. Eliontirus tripsacoides H. & B. Stems 6-15 dm, tall, from a rootstock, branched 
above: leaf-blades 5 dm. long or less, involute above the base when dry and about 0.8 
mm. in diameter, 3-5 mm. wide at the base, hirsute above near the base : racemes finally 
exserted, 7-14 cm. long, the rachis-internodes pilose excepting the inner surface : sessile 
spikelet 6.5-8 mm. long, about tAvice as long as the rachis-internode ; pedicellate spikelet 
5-6 mm. long, reaching or extending a little beyond the apex of the sessile spikelet, the 
pedicel pilose, excepting the inner surface. 

In low pine lands, Florida to Texas. Also in Mexico and South America. Summer and fall. 

8. SCHIZACHYRIUM Nees. 

< 

Annual or perennial grasses, tufted, or from rootstocks, with flat or involute leaf-blades, 
and spike-like racemes, singly disposed, terminating the stem or its branches. Spikelets 
in pairs at each node of the articulated and frequently hairy rachis, one sessile, the other 
pedicellate. Sessile spikelet of 4 scales, the outer 2 indurated, sometimes pubescent, the 
remainder of the scales hyaline, the fourth scale entire or 2-toothed at the apex, bearing a 
straight, contorted or spiral a^vn ; palet small, hyaline. Pedicellate spikelet sterile, of 1 
or 2 scales, or wanting. Stamens 1-3. Styles distinct. Stigmas plumose. Beakd Grass. 

Internodes of the racemes glabrous, or merely shortly appressed-pubescent on 
the back, the racemes hence appearing naked. 
Internodes as well as the first scale of the sessile spikelet glabrous. 

Sessile spikelet 5-6 mm. long ; pedicel stout, oblong-elliptic, the outer mar- 
gin ciliate its entire length. 
Sessile spikelet 4 mm. long; pedicel slender, linear, the outer margin ciliate 
only at the apex. 
Internodes as well as the first scale of the sessile spikelet appressed-pubes- 
cent. 
Internodes of the racemes and the pedicels long-ciliate on the margins, the in- 
ner or usually both surfaces glabrous, the racemes hence appearing hairy. 
Leaf-blades flat and broad ; rachis-internodes and pedicels glabrous on the 
back, or the former rarely sparsely pilose at the summit, the marginal 
hairs much shorter than the respective organs. 
Stems tufted, no stolons. 

Sheaths and leaf-blades glabrous or sometimes sparingly pubescent. 
Spikelets 5-7 mm. long. 
Spikelets 10 mm. long. 
Sheaths and leaf-blades densely long-villous. 6. S, vUlosissimum, 

Stems not tufted, stoloniferous, rootstocks long and slender. 

Pedicellate spikelet staminate : lower sheaths numerous, crowded, the 

blades spreading. 
Pedicellate spikelet sterile : lower sheaths few, not crowded, the blades 
erect. 
Sessile spikelet 6-7 mm. long, the first scale strongly tuberculate- 
roughened ; pedicellate spikelet of a single scale, about S-mm. 
long, sing]e-awned. 
Sessile spikelet 9-10 mm. long, the first scale smooth or nearly so ; 
pedicellate spikelet of 2 scales, 6-8 mm. long, the first scale 3- 
awned. 

Leaf-blades involute, filiform ; rachis-internodes and pedicels strongly pilose 
on the back, the marginal and dorsal hairs much longer than the re- 
spective members. 10. 5. gracile. 

1. Sdifzachyrluxn semib^rbe Xees. Smooth and glahrous. Stems tufted, 6-12 dm. 
tall, the branches in I's or 2's : leaf -blades 3 dm. long or less, 2-5 mm. wide : racemes 
single, 5-8 cm. long, partially included at the base, the rachis-internodes with a dense 
ring of short hairs at the base, thick, channeled on the inner surface : sessile spikelet 5-6 
mm. long, the first scale rounded on the back, roughened, acuminate, the awn of the fourth 
scale 12-15 mm. long, geniculate, tightly spiral at the base, the column exserted ; pedicel- 
late spikelet consisting of a single hispidulous scale about 3 mm. long with an equally long 
awn, the pedicel stout, oblong-elliptic, ciliate on the outer margin, shorter than the inter- 
node. {_Andropogo7i semiberbis (Nees) Kunth.] 

In dry rocky or sandy ground, southern peninsular Florida. Also tropical America. Summer. 

2. Schizachyrium t6nerum Nees. Smooth and glabrous. Stems tufted, slender, 
often weak and decumbent, 4-10 dm. long, the branches in I's or 2^8 : leaf-blades 2 dm. 
long or less, 0.5-2 mm. wide, the lower ones often sparingly hirsute above near the base : 
racemes single, 3-6 cm. long, the rachis-internodes with a ring of hairs at the base, stout, 



1. S, semihcrbe^ 

2. S, tenerum, 

3. S. oligostachyum. 



4. S. scoparium, 

5. S, amiminatum. 



7. 5. maritimum. 



8. S. stoloniferum. 



9. S, inaristaium. 



rOACEAE 



59 



channeled on tlie inner surface : sessile spikelet about 4 mm. long, the first scale somewliat 
rounded on the back, acute, the awn of the fourth scale 7-10 mm. lon^^, geniculate, tightly 
spiral at the base, the colnmn exserted ; pedicellate spikelet consisting of a single scale, 
4-5 mm. long, awnless or awn-pointed, tlie pedicel linear, not stout, i)iIose on the outer 
side near the summit, usually equalling or a little exceeding the internode. {^Andropoc/on 
tencr (Nees) Kunth.] 

In dry ground, South Carolina to Florida and southern Texas, Also in tropical America. Fall. 

3. Schizachyrium oligost^chynm (Chapm. ) Nash. Smooth and glabrous, some- 
times glaucous. Stems 9-15 dm. tall, the branches in I's or 2's : leaf-blades 2 dm. long or 
less, 4 mm. wide or less : racemes single, usually partially included at the base, 6-10 cm. 
long : sessile spikelet about 6 mm. long, about as long as or a little exceeding the hirsute 
rachis-internode, the first scale hirsute, the geniculate awn of the fourth scale 10-12 nun. 
long, closely spiral at the base, the column considerably exserted ; pedicellate spikelet 
4-5 mm. long, the first scale glabrous, bearing an awn about 2 mm. long. \_Andropo(}on 
oUgostachyus Chapm.] 

In dry sandy soil, Florida. Fall. 

4. Schizachyrium scop^rium (Miclix.) Nash. Green or purplish, sometimes 
glaucous. Stems tufted, 4.5-15 dm. tall, the branches in rs-4's : leaf-sheaths usually 
glabrous, sometimes more or less hirsute ; blades 5 dm. long or less, 8 mm. wide or loss, 
commonly roughened, and frequently somewhat hirsute above near the base : racemes 



Single, 3-6 cm. long, the hairs on the rachis-internodes and pedicels grayish Avhite : ses- 
sile spikelet 5-7 mm. long, usually about twice as long as the internode, the first scale 
generally more or less tuberculate-roughened, the awn of the fourth scale geniculate, 
8-15 ram. long, closely spiral at the base, the column exserted ; pedicellate spikelet 2-4.5 
mm. long, the first scale usually glabrous, tipped with an awn generally 1 mm. long or less, 
the pedicel considerally shorter than the sessile spikelet. \_A71djvpogon scopariiis Michx.] 
In dry sandy soil, New Brunswick to Alberta, Florida and Texas. Summer and Fall. Broom Grass. 

5. Schizachyrium aounun^tum Nash, Stems tufted, 7-10 dm. tall, the branches 
in l's-3'8 : leaf-sheaths generally rough toward the summit, compressed, keeled ; blades 
2 dm. long or less, 5 mm. wide or less, rough : racemes single, finally exserted, 3-6 cm. 
long, the hairs of the rachis-internodes and pedicels grayish white : sessile spikelet 1 cm. 
long, about twice the length of the internode, the awn about 1.5 cm. long, geniculate ; 
pedicellate spikelet consisting of 2 scales, the first 4-5 mm. long, strongly hispidulous and 
bearing an awn 2 mm. long or less, the pedicel about § as long as the sessile spikelet. 

In dry soil, Mississippi. Fall. 

6. Schizachyrium villosfsslmum (Kearn.) Nash. Leaf-sheaths, and blades on both 
surfaces, densely villous. Stems tufted, 8-10 dm. tall, rather stout : leaf -blades 3.5 dm. long 
or less, 3-5 mm. wide, erect, rather firm : racemes single, about 3 cm. long, exserted from 
the spathes which are more or less villous : sessile spikelet about 6.5 mm. long, the first 
scale tuberculate-roughened, acuminate, the awn of the fourtJi scale usually geniculate and 
more or less contorted, 10-13 mm. long, tightly spiral at the base, the column exserted ; 
pedicellate spikelet consisting of a single scale about 2 mm. long with an awn 1-2 mm. 
long, the pedicel recurved, at least when dry, shorter than the sessile spikelet, pilose above 
the middle with white hairs, glabrous below. lAndropogon scopariua villosi^simus Kearn.] 

In dry sandy soil, Mississippi. Fall. 

7. Schizachyrium marftimum (Chapm.) Nagh. Smooth and glabrous, glaucous. 
Stems 4-6 dm. tall : leaf-sheaths compressed, keeled, the lower ones crowded and over- 
lapping ; blades 1 dm. long or less, 4 mm. broad or less, widely spreading : racemes 
single, usually partially included at the base, 3-4 cm. long, rather stout, the terminal hairs 
of the internodes of the rachis 5-7 mm. long : sessile spikelet 8-9 mm. long, about twice 
as long as the internodes, the awn twisted at the base, geniculate, 9-13 mm. long ; pedicel- 
late spikelet 5-7 mm. long, awnless, consisting of four scales, the outer two acuminate and 
usually awn-pointed, the fourth scale enclosing a staminate flower, the peilicel about ^ as 
long as the sessile spikelet. [Andropogon maritbnus Chapm.] , 

Along the seacoast, western Florida to Mississippi. Fall. 

8. Schizachyrium stoloniferum Xash. Stems 6-10 dm. tall, stoloniferous : leaf- 
sheaths keeled, more or less hirsute on the margins near the summit ; blades 2 dm. long 
or less, 2-5 mm. wide, smooth beneath, rough above and hirsute near the base: racemes 
single, 3-4 cm. long : sessile spikelet 6-7 mm. long, acuminate, about twice as long as the 
rachis-internode, the first scale strongly tuberculate-roughened, the awn of the fourth scale 
geniculate, more or less contorted, 8-10 mm. long, spind at the base, the column not ex- 
serted ; pedicellate spikelet of a single scale about 3 mm. long, hispidulous, bearing an 
awn shorter than itself. 

In sandy soil, western Florida. Fall. 



60 



POACEAE 



9. Schizachyrium triaristatum Xash. Stems 6-8 dm. tall, stoloniferous : leaf- 
sheaths keeledj more or less hirsute on the margins near the summit ; blades 1.5 dm. long 
or less, 3-5 mm. Avide, hirsute above near the base : racemes single, 3-5 cm. long : sessile 
spikelet 9-10 mm. long, acuminate, more than twice as long as the rachis-internode, the 
first scale smooth or nearly so, the aAvn of the fourth scale 12-15 ram. long, geniculate, 
more or less contorted, spiral at the base, the column not exserted ; pedicellate spikelet of 
2 scales, 6-8 mm. long, the first scale hispidulous, 3-awned. 

In sand» Florida. Fall. 

10. Schizachyrium gracile (Spreng. ) Xash. Smooth and glabrous. Stems densely 
tufted, slender, rigid, 3-6 dm. tall ; leaf-blades 2 dm, long or less, very slender, involute, 
0.5 mm. in diameter or less: racemes long-exserted, single, 3-5 cm. long, silvery white: 
sessile spikelet 5-6 mm, long, about h again as long as the internode, the awn geniculate, 
13-20 mm. long, tightly spiral to the bend, loosely so above, the column much exserted : 
pedicellate spikelet consisting of a single scale, 1-2.5 mm. long, short -awned, the pedicel 
about as long as or a little shorter than the sessile spikelet. \_Andropogon gracilis Spreng.] 

In dry pine woods, southern peninsular Florida; also in the AVest Indies. Summer. 



4 

h 



9. ANDROPOGON L. 

Perennial grasses, tufted or from elongated rootstocks, with flat or involute leaf -blades, 
and spike-like racemes, disposed in pairs or sometimes in 3's or more, terminating the stem 
or its branches, and often protruding from the side of a membranous spathe-like sheath. 
Spikelets sometimes with a ring of short hairs at the base, in pairs at each node of the 
articulated and frequently hairy rachis, one sessile, the other pedicellate. Sessile spikelet 
of 4 scales, the outer 2 indurated, often pubescent, the remainder of the scales usually 
hyaline, the fourth scale entire or 2-toothed at the apex, bearing a straight contorted or 
spiral awn, or sometimes awnless ; palet small, hyaline. Pedicellate spikelet usually sterile 
of 1 or 2 scales, sometimes of four scales and enclosing a staminate or more rarely a perfect 
flower, or frequently entirely wanting, the first scale rarely short-awned. Stamens 1-3. 

Styles distinct. Stigmas plumose. Beard Grass. Broom Grass. Saxd Grass. 

A. Pedicellate spikelet sterile, consisting of 1 or 2 scales, much smaller than the 
sessile one. 
a. Stamen 1. 

1. Racemes usually equalling or a little shorter than the spathes, rarely 
somewhat exceeding them (considerably exserted in some forms of 
no. 2), the common peduncle thus concealed. 
Inflorescence oblong to oval or obovate, the branches many times di- 
vided, the lower ones elongated, forming: 1 or more corymbiform 
masses ; upper stem-leaves usually equalling or exceeding the in- 
florescence, 
Spathes smooth ; apex of the common peduncle of the racemes gla- 
brous. 
Spathes verj' rough ; apex of the common peduncle of the racemes 
hispidulous. 
Inflorescenee long and narrow, commonly linear, the branches not 
much divided nor the lower ones excessively elongated, hence 
forming no corymbiform masses ; upper stem-leaves usually shorter 
than the inflorescence. 
Racemes in pairs (very rarely in 3's or 4's). 
Sheaths not glabrous. 

Sheaths hirsute on the margins, the upper surface of the leaf- 
blades also hirsute near the base ; hairs on the summit of 
the internodes of the racemes rather sparse, and about 
twice their length, 
Sheaths, especially those of the innovations and their blades, 
densely appressed-hirsute ; hairs on the summit of the 
internodes of the racemes copious and about three times 
their length. 
Sheaths glabrous. 

Leaf-blades tuberculate-hirsute above toward the base ; hairs 

of the racemes dense, the spikelets therefore obscurely 

visible. 

Leaf-blades not hirsute above; hairs of the racemes rather 

scant, the spikelets therefore plainly visible. 

Branches of the inflorescence several times divided : spathes 

2-3 cm. long. 
Branches of the inflorescence simple : spathes 4-7 cm. long. 
Stems slender ; basal leaf-blades narrow, 2 mm. wide or 

less, usually long and flexuous. 
Stems stout ; basal leaf-blades broad and rigid, 3-6 mm. 
wide. 
Racemes in 4's (rarely in 2's or 3's) ; sheaths, at least the lower ones, 
densely hirsute. 



1, A. glomeroius. 

2. A. corymbosus. 



3. A, Virginicus. 



4. A, longiberbis. 



5. A, Tracyi. 



6. vl. capillipes. 



7. A. perangustatits. 

8. A, glaucopsis. 



POACEAE 



61 



Spathes narroiv, long-acuminate, much exceeding the slender ra- 
cemes : sessile spikelet 3-1 mm. long, lanceolate. 9. A. tetrasiachyus, 
Spathes broad, acuminate, equalling or shorter than the stout 
racemes : sessile spikelet ahout 4.5 mm. long, broadlv lanceo- 
late. ' 10. ^. MohriL 
2. Racemes, at least some of them, entirely exserted from the spathes. the 
common peduncle thus visible. 

Sheaths at the summit of the stem and also sometimes at the upper 
nodes much enlarged, crowded and imbricated. 
All the flowering stems with enlarged upper sheaths ; lower sheaths 
shorter than the internodes, hence distant. 
Basal sheaths and those of the innovations glabrous ; enlarged 

sheaths in 2's or 3's, 3 mm. wide or less. 11. A, gracilior. 

Basal sheaths and those of the innovations densely hirsute ; en- 
larged sheaths in 4's or more, 4-6 mm. wide. 12. A. ElliottiL 
Only some of the flowering stems with enlarged upper sheaths ; lower 

sheaths much exceeding the internodes, hence overlapping, 13. A, campylorachcns. 
Sheaths not enlarged. 

Spathes exceeding 10 cm. in length : racemes long and lax, the inter- 
nodes much exceeding the spikelets. 13, A, campyloraduus, 
Spathes less than 8 cm. long : racemes short and stout, the internodes 
equalling or shorter than the spikelets. 
Inflorescence much branched, branches much divided ; sheaths 
glabrous. 
Eacemes 1-2 cm. long, the spikelets about twice as long as the 

rachis-internodes. 14. A. bi-achystachyns. 

Racemes 3-4 cm. long, the spikelets equalling or little exceed- 
ing the rachis-internodes. 15. A. Flaridanus. 
Inflorescence not much branched, the branches little or not at all 
divided. 
• Sheaths glabrous; racemes silvery white. 16. A, subtcnuis. 
Sheaths hirsute ; racemes brown. 17, A. arctatus, 
b. Stamens 3. 

First scale of the sessile spikelet appressed-hispid between the keels, rather 
thin : sheaths sometimes pubescent. 
First scale nerveless between the keels, or if intermediate nerves occur, 
not running the entire length of the scale : terminal hairs of the 
internodes about twice their length. 18. A. argyraeus. 

First scale with 2 or 3 nerves between the keels, the nerves running the 
entire length of the scale: terminal hairs of the internodes about 
equalling them. 19. A. Cabanisii. 

First scale of the sessile spikelet glabrous and shining between the keels, 

firm : sheaths glabrous, and, with their blades, glaucous. 20. A. Scribnerianus, 

B. Pedicellate spikelet as large as the sessile, or larger, consisting of 4 scales and 
a staminate or rarely perfect flower. 
Stems tufted, no rootstocks. 

Rachis-internodes of the racemes smooth : pedicellate spikelet staminate. 
Outer 2 scales of the sessile spikelet more or less hispidulous all over : 

hairs on the internodes usually 2 mm. long or less. 21. A, furcatus. 

Outer 2 scales of the spikelet glabrous, excepting the nerves and also 
toward the summit of the first scale : hairs on the internodes 3-4 
mm. long, usually yellow. 22. A, chrysocamus. 

Rachis-internodes of the racemes strongly hispidulous : pedicellate spike- 
let perfect. 23. A, Tciinesseenm. 
Stems from long horizontal rootstocks, 24. A. geminatus, 

1. Andropogon glomer^tus (Walt.) B.S,P. Stems 6-15 dm. tall, commonly 
stout, the branches repeatedly and fastigiately branched, the lower ones somewhat elon- 
gated but considerably shorter than the stem, thus forming a large oblong glomerate pan- 
icle: leaf -blades 4 dm. long or less, 7 mm. wide or less, rough: spathes 2.5-3 cm. long, 
equalling or somewhat exceeding the racemes, smooth and glabrous, fastigiately crow^ded 
at the summit of the stem and ends of the branches : racemes in pairs, 1-2 cm. long : 



sile spikelet 3-4 mm. long, the awn 10-15 mm. long, straight ; pedicellate spikelet want- 
ing, or present as a subulate rudimentary scale. [-4, macrouras Miehx.] 

In low ground, Florida to Texas, New Mexico and Mexico. Fall.— A form with the racemes usu- 
ally more or less exserted from the apex of the narrow spathes which are tightly enrolled on the com- 
mon peduncle of the racemes, is known as A. glomeratus tenuispdthens Nash. 

2. Andropogon cor3^nb6sus (Chapm. ) Nash. Stems 4-10 dm. tall, rather stout, 
from a little exceeding to twice as long as the basal leaves, the branches much divided, 
the lower ones elongated and nearly equalling the upper, thus forming a corymbiform 
panicle : leaf-sheaths keeled, those at the base much compressed and equitant, rough, often 
more or less papillose-hirsute, especially the shorter and crowded ones of the inflorescence ; 
stem-leaves with blades 3 dm. long or less, 5 mm. wide or less, rough : spathes very rough, 
narrow, tightly enrolled around the common peduncle of the raceme which is densely his- 
pidulous toward the summit and rather stout : racemes in pairs, more or less exserted from 
the summit of the spathes, 2-3 cm. long: sessile spikelet 4-5 mm. long, the awn 12-13 
mm. long, straight or nearly so ; pedicellate spikelet usually present as a subulate scale 
1-2 mm. long, [^. macrmirus var. corymbosv^ Chapm.] 

In wet soil, District of Columbia to Florida and Mississippi. Fall.— A form differing from the type 
in having the spathes generally about equalling the racemes and few if any of them narrow and in- 
rolled on the peduncles is known as A, corymbosns abbreiidtun (Hack.) Nash. It ranges as far north as 
Long Island, N. Y. 



62 



POACEAE 



3. Andropogon Virginicus L. Stems tufted, 5-10 dm. tall, the branches in l's-3's : 
leaf-sheaths, at least the lower ones, more or less tuberculate-hirsute on the margins with 
long usually lax hairs ; blades 4 dm. long or less, 2-5 mm. wide, rough or roughish, hirsute 
on the upper surface near the base : spathes 3-5 cm. long, extending beyopd the racemes : 
racemes generally in pairs, rarely in 3's or 4^s, 2-3 cm. long: sessile spikelet 3-4 mm, 
long, twice to i again as long as the internode, the awn straiglit, 10-15 mm, long ; pedi- 
cellate spikelet wanting, or rarely present as a minute scale, the pedicel exceeding the 
sessile spikelet. 

In dry or moist soil, Massachusetts to Pennsylvania, Illinois, Florida and Texas. Fall. 

4. Andropogon longib6rbis Hack. Stems tufted, 5-10 dm. tall, the branches in 
l's-3's : leaf-sheaths, especially those on the innovations, appressed-hirsute, shorter than 
the internodes ; blades 5 dm. long or leas, 7 mm. wude or less, those on the innovations 
densely appressed-hirsute, those on the stem more or less so beneath, rough above : spathes 
3-5 cm. long, usually considerably exceeding the racemes, commonly brown : racemes in 
pairs, 3-4 cm. long, stout: sessile spikelet 4-4.5 mm. long, about twice as long as the 
rather stout rachis-internode, the awn straight or nearly so, 12-16 mm. long ; pedicellate 
spikelet a subulate scale, or wanting, the pedicel rather stout and a little exceeding the 
sessile spikelet. 

In dry pine lands, eastern and peninsular Florida. Spring and sumraer. 

5. Andropogon Ttkoyi Nash. Stems 5-8 dm. tall, the branches in I's or 2's : leaf- 
sheaths smooth and glabrous ; blades 2 dm. long or less, 1-2.5 mm. wdde, smooth beneath, 
rough above and hirsute toward the base : spathes 4-5 cm. long, rather broad, from slightly 
shorter to exceeding the racemes : racemes in pairs, 3-4 cm. long, rather stout : sessile 
spikelet 5 mm. long, about twice as long as the stout internode which is densely clothed 
with silvery white hairs a little more than IJ times as long as the spikelet, the awn 1.5-2 
cm. long, sometimes a little spiral at the base ; pedicellate spikelet wanting, or present as a 
minute rudimentary scale, the pedicel exceeding the sessile spikelet. 

In dry soil, Alabama and Mississippi. Fall. 

6. Andropogon capillipes Nash. Smooth and glabrous, glaucous. Stems 8-12 dm. 
tall : leaf-sheaths on the branches and summit of the stem much narrower than the 
spathes, shorter than the peduncles which are usually in 3's and around which the sheaths 
are tightly enrolled, the peduncles usually manifestly exserted ; blades 2 dm. long or less, 
1-2.5 mm, wade, erect: spathes 2-3 cm. long, exceeding the racemes: racemes 1.5-2 cm. 
long: sessile spikelet 3-3.5 mm. long, about twice as long as the internode, the awn 
straight, 11-13 mm. long : pedicellate spikelet wanting, or present as a minute rudimen- 
tary scale, the pedicel as long as or a little exceeding the sessile spikelet. 

In dry soil, North Carolina to Florida. Fall. 

7. Andropogon perangust^tus Nash. Smooth and glabrous, the basal leaves nar- 
row and flexuous, about ^ as long as the plant. Stems 2-8 dm. tall, slender, the branches 
usually single, sometimes in pairs : leaf -blades 3 dm. long or less, 1-2 mm. wide : spathes 
4-5 cm. long, extending beyond the summit of the racemes which are in pairs, 2.5-4 cm. 
long : sessile spikelet 3.5-4 mm. long, twice to J again as long as the internode, the awn 
12-18 mm. long ; pedicellate spikelet wanting or rarely present as a minute scale, the ped- 
icel exceeding the sessile spikelet. [^A. Virginicus var. stenophyllns Hack., not A. steaophyl- 
/usE. &S.] 

In dry soil, Florida to Mississippi. Fall. 

8. Andropogon glauc6psis (Ell.) Nash. Glaucous, grayish green. Stems 6-10 
dm. tall, rigid, rather stout, the branches in l's-2's, usually considerably above the middle : 
leaf-sheatlis smooth and glabrous, keeled, the lower ones compressed ; blades erect, 2 dm. 
long or less, 2.5-6 mm. wide, smooth and glabrous beneath, roughened above with a 
minute pubescence, the basal ones from J-J as long as the stems : spathes 4-6 cm. long, 
equalling or usually a little exceeding the racemes : racemes in pairs, 3-4.5 cm. long : sessile 
spikelet 4.5-5 mm. long, long-acuminate, from equalling to nearly twice as long as the inter- 
node, the awn 1.5-2 cm. long, straight; pedicellate spikelet wanting, or present as a 
rudimentary scale, the pedicel exceeding the sessile spikelet. \_A, maa^ourus var. glaucop- 
mEU.] 

In dry soil, North Carolina to Florida and Mississippi. Fall, 

I 

9. Andropogon tetrastdchyns Ell. Stems tufted, 8-15 dm. tall : leaf-sheaths 
densely villous, at least the lower ones, with dark hairs ; blades 4 dm. long or less, 2-4 
mm. wide, the lower ones villous on both surfaces toward the base : spathes 3-4, rarely 6, 
cm. long, extending beyond the racemes : racemes usually in 4's, sometimes fewer, 3-4 
cm. long : sessile spikelet 3-4 mm. long, twice to } again as long as the internode, the 
awn straight, 1.5-2 cm. long ; pedicellate spikelet wanting, or rarely present as a minute 



POACEAE 



63 



scale, the pedicel considerably exceeding the sessile spikelet. [A. Virginicus var. tetra- 
stachyus (Ell.) Hack.] 

In dry or moist soil, South Carolina to Florida and Alabama, Fall. 

10. Andropogon Mohrii Hack. Stems 8-12 dm. tall : leaf-sheaths densely ap- 
pressed-hirsute ; blades 3 dm. long or less, 5 mm. wide or less, densely appressed-hirsute : 
spathes 4-5 cm. long, equalling or a little shorter than the racemes : racemes in 4's, 3-4 
cm. long, rather stout, the hairs at the summit of the rachis-internodes i again as long as 
the spikelets : sessile spikelet about 4.5 mm. long, about twice as long as the internode, 
the awn straight or nearly so, slightly if at all twisted at the base, 2-2.5 cm. long ; pedicel- 
late spikelet wanting, or sometimes present as a small subulate scale, the pedicel usually a 
little shorter than the sessile spikelet. 

In low pine lands, western Florida to Louisiana. Fall. 

11. Andropogon gracflior (Hack.) Nash. Stems tufted, slender, 3-7 dm. tall, 2-3 
times as long as the basal leaves, the lower branches single : leaf -sheaths glabrous, shorter 
than the internodes, the terminal ones more or less enlarged, 5-7 cm. long, 2-3 mm. wide ; 
stem-leaves with blades 1.5 dm. long or less, 1-2 mm. wide, smooth beneath, rough above 
and sparingly hirsute near the base : racemes in pairs, slender, about 3 cm. long, exserted, 
or slightly included at the base : sessile spikelet 3.6-4 mm. long, equalling or somewhat 
exceeding the internode, the awn geniculate, 1,3-2 cm. long, loosely spiral at the base, the 
column exserted ; pedicellate spikelet a minute rudimentary scale, the pedicel usually about 
^ again as long as the sessile spikelet. 

In dry or moist places, Florida to Alabama ; also in Tennessee. Fall. 

12. Andropogon Ellidttii Chapm. Stems tufted, 5-8 dm. tall, rather stout, 2-3 
times as long as the basal leaves : leaf-sheaths shorter than the internodes, the lower ones 
and those of the innovations densely appressed-hii^sute, those of the inflorescence much en- 
larged and densely crowded at the summit and also sometimes at the nodes below, 8-11 cm. 
long, 3-6 mm. wide ; blades 2 dm. long or less, 2-5 mm. wide, usually smooth beneath, 
rough above and hirsute near the base : racemes in pairs, slender, 3-4 cm. long, the longer 
one at each node exserted, the rest concealed in the spathes : sessile spikelet 4.5-5 mm. 
long, equalling or somewhat exceeding the internode, the awn geniculate, 1.5-2.3 cm. long, 
usually spiral at the base, the column much exserted ; pedicellate spikelet a minute rudi- 
mentary scale, the pedicel usually about J again as long as the sessile spikelet. 

In dr>' sandy soil. South Carolina and Tennessee to Florida and Mississippi. Fall. 

13. Andropogon campy lordcheus Nash. Stems densely tufted, 4-8 dm. tall, the 
terminal internode much elongated and slender, the branches single : leaf-sheaths much 
exceeding the internodes, overlapping, those on the stem 13-17 cm. long, sparingly hirsute, 
those on the innovations densely hirsute with ascending hairs, the terminal one very nar- 
row and tightly embracing the stem, the upper sheaths on some of the stems much en- 
larged and producing smaller spathes in their axils with concealed racemes ; blades erect, 
2 dm. long or less, 2-3 mm. broad, smooth beneath, hirsute above near the base : racemes 
in 2's-4's, flexuous, 5-10 cm. long: sessile spikelet 5 mm, long, usually much exceeded 
by the internode, the terminal hairs of which are 8-10 mm. long, the awn more or less 
contorted, 1.5-2 cm. long, barely if at all twisted at the base ; pedicellate spikelet wanting, 
or present as a minute rudimentary scale, the pedicel much exceeding the sessile spikelet. 

In dry sandy soil, southern peninsular Florida and Mississippi. Fall. 

14. Andropogon brachyst^chyua Chapm. Stems tufted, 6-15 dm. tall, the 
branches in l's-3'8 and usually pilose just below the nodes: leaf-sheaths smooth and 
glabrous ; blades erect, 3 dm. long or less, 3-4 mm. wide, smooth beneath, on the upper 
surface rough and hirsute near the base : racemes in pairs, shortly exserted, or partly in- 
cluded at the base, 1-2 cm. long : sessile spikelet 3-4.5 mm. long, about twice as long as 
the internode, the first scale pubescent between the keels, the awn of the fourth scale 
straight or nearly so, 6-9 mm. long ; pedicellate spikelet consisting of a single scale, the 
pedicel shorter than the sessile spikelet. 

In moist pine lands, Florida. Summer and fall. 

15. Andropogon Floridinus Scribn. Stems tufted, 5-16 dm. tall, tlie bninches in 
l's-3's : leaf-sheaths roughish, usually shorter than the internodes; blades 5 dm. long or 
less, 1 cm. wide or less, rough : racemes in pairs, occasionally in 3's or 4'8, 3-4 cm, long, 
exserted, or partly included at the base : sessile spikelet 3.5-4 mm. long, equalling or a little 
longer than the internode, the awn straight, 8-12 mm. long ; pedicellate spikelet wanting 
or present as a small scale, the pedicel exceeding the sessile spikelet. 

In dr>' pine lands, peninsular Florida. Summer and fall. 

16. Andropogon snbt^nuis Nash. Stems 3-6 dm. tall, slender, the branches single : 
leaf-sheaths smooth and glabrous; blades 1.5 dm. long or less, 1-2 mm. wide, smooth 



64 



rOACEAE 



beneath, rough above and somewhat hirsute near the base : racemes in pairs, exserted, or a 
little included in the narrow spathes, 2-3 cm. long: sessile spikolet 3-4 mm. long, exceed- 
ing the internode, the awn 1-1.5 cm. long, more or less contorted, slightly twisted at the 
baijc ; pedicellate spikelet wanting, or a minute rudimentary scale, the pedicel considerably 
exceeding the sessile spikelet. 

In sandy soil, Florida to Mississippi. Fall, 

17. Andropogoa arctAtus Chapm. Stems 1-1.5 m, tall, branched toward the sum- 
mit, the branches in l's-3's : leaf -sheaths, at least the lower ones, more or less densely 
appressed-hirsute at the summit ; blades erect, 3 dm. long or less, 5 mm. wide or less, the 
upper surface rough, the lower usually densely appressed-hirsute toward the base : racemes 
in pairs, rarely in 3's or 4's, rather stout, dark gray, 2.5-4 cm. long, long-exserted : sessile 
spikelet 5-6 mm. long, about twice as long as the internode, the awn more or less con- 
torted, 1-1.5 cm. long ; pedicellate spikelet usually present, consisting of a single scale, the 
pedicel considerably shorter than the sessile spikelet. 

In low pine lands, Florida. Fall. 

18. Andropogon argyra^us Schult. Stems tufted, 8-12 dm. tall, about twice as long 
as the basal leaves, the branches in l's-3's : leaf-sheaths smooth or rough, glabrous or 
hirsute ; blades 3 dm. long or less, 3 mm. wide or less, rough : racemes in paii-s, rather 
stout, silvery gray, 3-5 cm. long, long-exserted, the hairs on the summit of the internodes 
I2-2 times their length : sessile spikelet 5-6 mm. long, about twice as long as the inter- 
node, the first scale appressed-pubescent between the nerves, acuminate from about the 
lower third, nerveless between the keels and usually deeply depressed, the awn more or 
less contorted, 1.5-2.5 cm. long; pedicellate spikelet of a single scale, 1-3 mm. long, the 
pedicel usually a little shorter than the sessile spikelet. 

In dry soil, Delaware and Maryland to Florida, and Texas ; also in Indian Territory and Mis- 
somi, and probably southward to the Gulf. Fall. Silver Beard. 

19. Andropogon Cabanfsii Hack. Stems 6-10 dm. tall, the branches in I's or 2*s : 
leaf -sheaths smooth or a little roughened ; blades 2.5 dm. long or less, 2-4 mm. broad, 
smooth beneath, rough above : racemes in pairs, 4-7 cm. long, grayish, the hairs at the 



apex of the internodes as long as or a little exceeding them, rather scant : sessile spikelet 
6-7 mm. long, broadly lanceolate, tapering from the middle, about twice as long as the 
internode, the first scale strongly hispidulous and 2-3-nerved between the keels, the nerves 
running the entire length of the scale ; pedicellate spikelet of a single hispidulous scale 
3-3.0 mm. long, the pedicel about f as long as the sessile spikelet. 

In dry soil, Pennsylvania (according to Hackel) and Florida. Summer. 

20. Andropogon Scribneriinus Nash. Glaucous. Stems tufted, 3-10 dm. tall, 
twice as long as the basal leaves, rather sparsely branched above : leaf-sheaths shorter than 
the internodes, smooth and glabrous ; blades 1 dm. long or less, 2.5 mm. wide or less, the 
upper surface minutely pubescent and also often hirsute near the base : racemes in pairs, 
stout; long-exserted, 4-7 cm. long, bright silvery white, the hairs on the internodes copious, 
those at the summit about twice the length of the internodes : sessile spikelet 5-6 mm. 
long, about twice as long as the internode, the first scale narrowed from about the middle, 

[labrous and shining between the keels, the internerve flat or nearly so, the awn of the 
ourth scale more or less contorted ajid bent, somewhat twisted below, 1-1.5 cm. long ; 

pedicellate spikelet wanting, or present as a small scale 1.5 mm. long or less, the pedicel 

equalling or a little shorter than the sessile spikelet. 

In dry pine lands, Georgia and Florida. Spring and summer. 

21. Andropogon furc^tus Muhl. Stems 1-2 m. tall : leaf-sheaths glabrous or some- 
times slightly hirsute ; blades 6 dm. long or less, 12 mm. wide or less, smooth beneath and 
glabrous or rarely a little hirsute, more or less roughened above and hirsute at the base : 
racemes in 2's-6's, 5-10 cm. long, stout, long-exserted, the hairs of the internodes and 
pedicels grayish white, 1-2 mm. long : sessile spikelet 7-10 mm. long, the outer 2 scales 
more or less hispidulous, the awn 7-15 mm. long, geniculate, twisted at the base ; pedicel- 
late spikelet as large as or a little smaller than the sessile, staminate, awnless. 

In dry or moist soil, Maine and Ontario to Manitoba, Florida, Kansas and Texas. Summer and 
fall. 

22. Andropogon chryaocomns Nash. Stems 7-15 dm. tall, the branches in 
l'&-3's : leaf -sheaths smooth and glabrous ; blades 3 dm. long or less, 7 mm. wide or less, 
smooth beneath, a little roughened above : racemes in 2^s-4's, 5-9 cm. long, stout, long- 
exserted, the hairs of the internodes and pedicels about 3 mm. long, usually yellow : ses- 
sile spikelet about 1 cm. long, with a basal ring of short hairs, the outer 2 scales hispid on 
the nerves, the awn of the fourth scale twisted at the base, geniculate, 10-12 mm. long ; 
pedicellate spikelet awnless. 

In dry soil, Kansas to Texas, Summer and fall. 



POACEAE 



65 



23. Andropogon Tennesse^nsis Scribn. Stems 1-1.5 m. tall, stout, the branches 
in I's or 2's : leaf-sheaths, at least the loAver ones, liirsiite toward the summit ; bhides 6 
dm. long or less, 6-12 mm. wide, rough, the lower surface sometimes hirsute, and also the 
upper surface near the base : racemes in 2's-4's, 5-8 cm. long : sessile spikelet about 8.5 
mm. long, broadly lanceolate, twice as long as the hispidulous internode, the outer 2 
scales strongly hispidulous, the awn of the fourth scale geniculate, about 1.6 cm. long, 
twisted below, the column a little exserted ; pedicellate spikelet 8-10 mm. long, of 4 scales, 
perfect, the outer 2 scales strongly hispidulous, the first often short -awned, the hispidulous 
pedicel less than k as long as the sessile spikelet. 

In dry soil, Tennessee and Mississippi. Fall. 

24. Andropogon geminatus Hack. Smooth and glabrous, glaucous. Stems 6-10 
dm. tall, from long rootstocks : leaf-blades erect, rigid, long-acuminate, 3 dm. long or 
less, 9 mm. wide or less : racemes in pairs, finally exserted, 3-5 cm. long, rather slender, 
the hairs on the rachis-internodes and the pedicels grayish or yellowish white: sessile 
spikelet 6-8 mm. long, the awn not twisted below, geniculate^ 5-7 mm. long ; pedicellate 
spikelet about the same length, awnless. 

In dry soil, Texas. Summer. 

10. AMPHILOPHIS Nash/ 

Perennial grasses, with usually flat leaf-blades and showy often silvery white panicles, 
the axis short, making the panicle appear fan-like, or elongated with tlie branches scattered. 
Racemes usually numerous, the internodes with manifestly thickened margins, the median 
portion thin and translucent, the pedicels of the same construction, the margins ciliate 
with usually long hairs. Sessile S|)ikeletSiof 4 scales, the first one 2-keeled, the second 
1-keeled, the third and fourth scales hyaline, the latter very narrow, stipe-like, somewhat 
thickened, gradually merging into a usually geniculate contorted or spiral awn, or the awn 
rarely wanting. Pedicellate spikelets staminate and similar to the sessile, or sterile and 
smaller than them. Stamens 3. Styles distinct. Stigmas plumose. 

First scale of the sessile spikelet not pitted on the back, 
■ Axis of the panicle elongated, the branches scattered, the panicle hence linear 

to oblong ; stem-nodes naked. 
Sessile spikelets 3 mm. long, the awn wanting or rarely present and then but 

short and not twisted. 
Sessile spikelets 4 mm. long, the awn long and geniculate, spiral at the base, 2. A. Torreyanus. 
Axis of the panicle short, the branches congested, the panicle hence fan-like, 

oval or obovate; stem-nodes densely barbed. 3. A. barhinodis. 

First scale of the sessile spikelet with a deep pit-like impression on the back. 4. A. perforat us. 

1. Amphilophis exarlst^tus Nash. Smooth and glabrous. Stems 6-8 dm. tall, rather 
slender : leaf-blades 2 dm. long or less, 3-6 mm. wide, rough toward the apex : panicle 
10-13 cm. long, 2-2.5 cm. wide, oblong, its axis 8-10 cm. long, the branches much divided, 
the ultimate divisions (racemes) 1-2 cm. long, the terminal hairs 2-3 times as long as the 
rachis-internodes: sessile spikelet 3 mm. long, about ^ again as long as the internode, 
the fourth scale almost wanting, or present as a mere rudiment, very rarely short-awned ; 

/ pedicellate spikelet of a single scale, 2-3 mm. long, the pedicel considerably shorter than 
the sessile spikelet. [Andropogon saccharoides submiiticus Vasey, not A. siibmidicus Steud.] 

In dry soil, Texas. Summer. 

2. Amphilophis Torreyinus (Steud. ) Nash. Smooth and glabrous, glaucous. Stems 
5-10 dm. tall, simple or somewhat branched : leaf-blades 1-5 dm. long or less, 3-7 mm. 
wide, rough above : panicle 4-10 cm. long, 7-20 mm. wide, linear to oblong, its axis 2-7 
cm. long, the longer branches somewhat divided, tHe ultimate divisions (racemes) 1-4 cm. 
long, the terminal hairs 1^-2 times as long as tlie internodes : sessile spikelet 4 mm. long, 
about i again as long as tlxe internode, the awn geniculate, more or less contorted, 10-15 
mm. long, spiral at the base, the column much exserted; pedicellate spikelet consisting of 
a single scale, 2-3 mm. long, the pedicel shorter than the sessile spikelet. 

In dry soil, Kansas to Arizona, Texas and Mexico. Summer. 

3. Amphilophis barbinodis (Lag.) Nash. Stems tufted, 5-10 dm. tall, simple or 
somewhat branched, the nodes densely barbed w^th silvery hairs : leaf-sheaths and their 
blades smooth and glabrous, the latter 2 dm. long or less, 2-8 mm. wide, rough : panicle 
broadly oblong, ovate, oval or obovate, 5-12 cm. long, finally exserted, its axis 2-5 cm. 
lone^ ! mo^moa O-i .=; Q_p; /.m ir^nrr tlifi tprminal hairs twice as loner as the internodes: ses- 



1. A, exaristatus. 



sile spikelet 5-6 mm. long, about i again as long as the internode, the ger 

2-3 cm. long, spiral at the base, the column much exserted ; pedicellate spikel 

awnless scale, 4-5 mm. long, the pedicel considerably shorter than the sessile i 

In moist or rocky ground, central Texas to Arizona and Mexico. Summer and fall* 

5 



66 



POACEAE 



4. Amphilophis perforatus (Hack.) Nash. Stems tufted, 8-10 dm. tall, the nodes 
barbed : leaf-sheatlis and blades smooth and glabrous, or the latter with the upper sur- 
face pubescent with long scattered hairs ; blades 2 dm. long or less, 2-4 mm. wide : panicle 
6-8 cm. long, fan-shaped, much exserted : racemes 5-8, 6-6 cm. long, the terminal hairs 
about as long as the internodes; sessile spikelet 5-5.5 mm. long, the first scale with a 
deep depression on the back above the middle, the fourth scale with a geniculate awn 2-2.5 
cm. long, the column tightly spiral and much exserted ; pedicellate spikelet of a single 
awnless scale about 3 mm. long. 

In dry soil, Texas and Mexico. Fall. 

11. SORGHUM Pers. 

Tall grasses, with usually broad flat leaf -blades and large terminal panicles, its primary 
branches verticillate. Spikelets of 4 scales, in pairs, or in 3's at the end of the branches, 
one sessile and perfect, the rest pedicellate and staminate, dorsally compressed, pubescent or 

r 

glabrous. Sessile spikelets with the outer 2 scales indurated, the third and fourth hya- 
line, the latter awned or awnless. Pedicellate spikelets with the outer 2 scales firm-mem- 



/ 



branous, or rarely reduced to 1 or 2 scales and sterile. Lodicules ciliate. Stamens 3. 
Styles distinct. Stigmas plumose. 

1. Sorghtun Halep^nse (L. ) Pers. Smooth and glabrous. Stems 5-15 dm. tall, 
from a long rootstock : leaf-blades 5 dm. long or less, 0.5-3 cm, wide ; panicle 1.5-5 dm. 
long, oblong to oval, its branches ascending, the longer ones 7-14 cm. long : sessile spike- 
let 4.5-5.5 mm. long, ovate, the outer 2 scales densely appressed-pubescent with silky hairs 
and indurated at maturity, the first scale 3-toothed at the apex, the readily deciduous awn 
of the fourth scale 1-1.5 cm, long, geniculate, spiral below, the column much exserted; 
pedicellate spikelet 5-7 mm. long, lanceolate, the 2 outer scales sparingly pubescent. 

In fields and waste places, Pennsylvania to Kansas, Florida and Texas. Summer and fall* 

JOHNSON-GKASS. 

12. SORGHASTRUM Xash. 

Usually tall perennial grasses, with flat leaf-blades and terminal panicles with the prim- 
ary branches usually solitary and branched from the base, hence appearing as if whorled. 
Sessile spikelets dorsally compressed, of 4 scales, the outer 2 indurated, often hairy, the 
third and fourth scales hyaline, the latter long-awned, the awn spiral at the base. Pedi- 
cellate spikelets wanting, or very rarely present as a minute rudiment, usually only the 
hairy pedicels present, a single one at the side of each sessile spikelet, or 2, one on each 
side, at the end of the branches. Lodicules glabrous. Stamens 3. Styles distinct. 
Stigmas plumose. 

Awn but once bent, 1-1.5 cm. long, the closely spiral portion but little exserted be- 
yond the scales. 
Awn twice bent, 2-3 cm. long, the closely spiral portion extending to the second 
bend and much exserted beyond the scales. 
Branches of the panicle much exceeding the internodes of the axis, the ulti- 
mate divisions of its branches straight. 
Branches of the one-sided panicle shorter than the internodes of the axis, the 
ultimate divisions of the branches much curved, the spikelets hence re- 
flexed. 3. S. secundum. 

1. Sorghastnim nutans (L. ) Nash. Stems 1-2.5 m. tall : leaf-sheaths usually 
smooth and glabrous, or the low^ermost ones sometimes pubescent ; blades 6 dm. long or 
less, 13 mm. wide or less, very rough : panicle 2-5 dm. long, loose, the apex usually nod- 
ding, its branches erect or nearly so, at least the lower ones much exceeding the internodes 
of the axis, 7-10 cm. long, the ultimate divisions straight : spikelet 6-8 mm. long, lance- 
olate, the 2 outer scales golden brown and indurated at maturity, the first one densely 
pubescent with long erect hairs, the awn of the fourth scale geniculate, 1-1.5 cm. long, 
closely spiral to the bend, thence loosely twisted, the column more or less exserted ; ped- 
icel from 2-§ as long as the spikelet. [Sorghum avenaceum (Michx.) Chapm.] 

In dry or moist soil, Ontario to Manitoba, Rhode Island, Florida, Texas and Arizona. Late sum- 
mer and fall. Indian Grass. 

2. Sorghastnim Llnnaeanum (Hack.) Nash. Stems 1-1.5 m. tall: leaf -sheaths 
smooth and glabrous ; blades 4 dm. long or less, 1 cm. wide or less, very rough ; panicle 
1.5-3 dm. long, the apex usually nodding, its branches erect or nearly so, at least the 
lower ones much exceeding the internodes of the axis, 6-8 cm. long, the ultimate divisions 



1. S. nutans. 



2. S, Llnnaeanum, 



straight: spikelet 5.5-7.5 mm. long, lanceolate, the 2 outer scales blackish brown and in- 
durated at maturity, the first one densely pubescent with long erect hairs, the awn of the 



POACEAE 



67 



fourth scale twice bent, 2-3 cm. long, closely spiral to the second bend, thence loosely 
twisted, the column very much exserted ; pedicel from f as long as the spikelet to nearly 
equalling it. \_Sorghum nutans Chapm.] 

In dry soil, South Carolina and Tennessee to Florida and Mississippi. Full. 

3. Sorghastnim seciindum (Ell.) Nash.. Stems 8-14 dm. tall : leaf-sheaths smooth 
and glabrous ; blades 6 dm. long or less, 7 mm. wide or less, smooth beneath, rough above, 
often involute ; i)anicle 2-4 dm. long, one-sided, its branches erect or nearly so, rarely 
exceeding 4 cm. in length, usually shorter than the internodes of tlie axis, the ultimate 
divisions much curved, making thespikelets reflexed : spikelet 6-8 mm. long, lanceolate, 
the 2 outer scales golden brown and indurated at maturity, the first one pubescent with 
long erect hairs, the awn of the fourth scale twice bent, 2.5-3 cm. long, closely spiral to the 
second bend, thence loosely twisted, the column veiy much exserted ; pedicel from ^-f as 
long as the spikelet. [Sorghum secundum (Ell.) Chapm.] 

In dry sandy soil, Georgia and Florida. Fall. Wild Oats. 

J 

13. VETIVERIA Thouars. 

Tall grasses Math simple stems, narrow leaf-blades and terminal panicles with the 
branches usually much articulated and disposed in dense whorls. Spikelets in pairs, 
narrow, acute, of 4 scales, the one sessile and perfect, the other pedicellate and staminate. 
Sessile spikelets usually somewhat laterally compressed, the first scale coriaceous or char- 
taceous, the margin inflexed or involute, the second awned or awnless, the third and fourth 
scales hyaline, the latter entire or shortly 2-toothed, mucronate or awned from between the 
teeth. Pedicellate spikelets usually awnless, rarely awned. Stames 3. Styles distinct. 
Stigmas plumose. 

1. Vetiveria zizanloides (L. ) Nash. Stems 2 m. tall or more : sheaths smooth and 
glabrous ; blades 9 dm. long or less, 4-10 mm. wide : panicle 2-3 dm. long, its slender as- 
cending or nearly erect branches in dense whorls and readily disarticulating at the nodes : 
sessile spikelet about 4 mm. long, about as long as the intemode, the first scale minutely 
tuberculate-roughened, 2-keeled, the keels muricate, the second scale 1 -keeled, the keel 
muricate, the fourth scale awnless or short-awned, the awn not exserted beyond the 2 outer 
scales ; pedicellate spikelet about as long as or a little shorter than the sessile, the 2 outer 
scales sparingly muricate. 

Cultivated and escaping into fields in Louisiana. Fall. 

14. RHAFHIS Lour. 

Perennial or rarely annual "grasses, with narrow leaf-blades and terminal panicles, 
whose branches usually bear clusters of 3 spikelets, or very rarely more, at the end, one 
spikelet sessile and perfect, the other 2 staminate or sterile and pedicellate. Sessile spike- 
lets usually somewhat laterally compressed, of 4 scales, the first scale broadly involute, the 
second somewhat distinctly keeled, and usually awned, the third and fourth scales hyaline, 
the latter usually awned. Pedicellate spikelets dorsally compressed, awnless or awned. 
Stamens 3. Styles distinct. Stigmas plumose. 

1. Rhaphis pauciflonis (Chapm.) Nash. Annual. Stems 6-12 dm. tall, simi)le or 
somewhat branched : leaf -blades 2 dm. long or less, 2-10 mm. wide, papillose-hirsute 
above : panicle 2-3 dm. long, its branches erect or ascending, slender, the lower in whorls 
of 2-5, rarely divided, the longer, exclusive of the spikelets and awn, 5-8 cm. long : ses- 
sile spikelet about 15 mm. long, including the 6-7 mm. long and densely pubescent callus, 
cylindric or slightly laterally compressed, the first and second scales dark brown, shining 
and coriaceous at maturity, hispidulous at the apex, the fourth scale emitting? a flexuous 
more or less contorted usually geniculate awn 14-16 cm. long ; pedicellate spikelet 10-12 
mm. long, on slender pedicels about reaching the apex of tlie sessile spikelet, empty or 
containing a staminate flower. [Sorghum pauciflorum Chapm.] 

In dry sandy soil, eastern and peninsular Florida. Also in Cuba. Fall. 

15. HBTEROPOGON Pers. 

Annual or perennial grasses, sometimes tall, with narrow leaf-blades and compressed 
sheaths, and terminal solitary dense racemes. Spikelets 1-flowered, in pairs at the rachis- 
nodes, one sessile and fertile, the other pedicellate, containing a staminate flower, or empty. 
Scales of the sessile spikelets 4, the outermost empty, firm, convolute, awnless, the second 
also empty, thinner, keeled, the third scale very thinly hyaline, likewise empty, the 



68 



POACEAE 



fourth scale, enclosing a pistillate flower, small and hyaline and bearing a long rigid con- 
torted and geniculate awn ; palet small and hyaline, or wanting. Pedicellate spikelet awn- 
less, the outermost scale thinner than the corresponding one in the sessile spikelet. Sta- 
mens 3. Styles distinct. Stigmas plumose. 

Upper sheaths tuberculate along the keel and the first scale of the pedicellate 

spikelet on the midnerve, the latter 1.5 cm. long or more and glabrous. 1. H. mdanocarpuu , 

Upper sheaths and the first scale of the pedicellate spikelet smooth all over, the 
latter 1 cm. long or less, papillose-hispid toward the summit and near the 
margins. 2, H, contortus, 

1. Heteropogon melanocirpus (Muhl. ) Ell. Annual. Stems 4-15 dm. tall, much 
branched ahove : upper leaf-sheaths at least tuberculate on the keel ; blades 5 dm. long or 
less, 3-12 mm. wide : racemes 3-6 cm, long, exserted, or included at the base, the pedun- 
cles pilose with ascending hairs, the internodes between the upper spikelets densely pu- 
bescent with long chestnut-brown hairs : sessile spikelet 5-6 mm. long, the awn 9-15 cm. 
long ; pedicellate spikelet 15-22 mm. long, sterile or staminate, the first scale long-acumi- 
nate, tuberculate on the midnerve. [_ff. acuminatus Trin.] 

In cultivated grounds. South Carolina to Florida, Texas, Arizona and Mexico. Also in tropical 
America, Summer and fall. 

2. Heteropogon contdrtus (L. ) Beauv. Perennial, Stems 2-8 dm. tall, rather 
sparingly branched above : leaf-sheaths smooth, even on the keel ; blades 2 dm. long or 
less, 3-7 mm. wide : racemes 4-6 cm. long, exserted, or included at the base, the peduncles 
hispidulous, the internodes between the upper spikelets densely pubescent wath long nearly 
appressed chestnut-brown hairs: sessile spikelet 5-6 mm. long, the awn 4.5-8 cm. long; 
pedicellate spikelet about 1 cm. long, sterile or staminate, the first scale acute, papillose- 
hispid toward the summit and near the margins with long hairs. 

In dry soil, southern and western Texas to Arizona and Mexico. Widely distributed in the warmer 
parts of all countries. Spring to fall. 

16. HILARIA H.B.K. 

Stoloniferous grasses, decumbent and branching at tlie base, with flat or convolute 
leaf-blades and spicate inflorescence, Spiklets in sessile deciduous crowded clusters of 3, 
the empty scales resembling an involucre, the central spikelet 1 -flowered, the flower pistil- 
late or perfect, the lateral spikelets 2-flowered, the flowers staminate. Scales 4, the 2 outer 
empty, rigid, thin or indurated, the first the larger and varying much in shape, entire 
or 2-cleft at the toothed or lacerate apex, awnless, or bearing an awn between the lobes, 
the second scale narrower, often keeled, entire or 2-toothed at the apex, awnless, mucronate, 
or fihort-awned ; third and fourth scales thin-membranous, entire or toothed at the apex, 
each in the lateral spikelets enclosing a palet and a flower, in the central spikelet the third 
scale is empty. Stamens 3. Styles a little united at the base. Stigmas shortly plumose. 

Outer scales of the spikelet linear or oblong, the nerves parallel, some of them awned. 1. H, Texana. 
Outer scales of the spikelet cuneate, the nerves strongly diverging above, awnless. 2. JT. mutica. 

1. Hilarla Texana (Vasey) Nash. Creeping by arched stolons. Stems 1-2.5 dm. 
tall : basal leaves numerous ; blades 1-5 cm, long and about 2 mm. wide, very rough, pu- 
bescent, the upper surface densely so with short hairs, the lower surface with a few long 
hairs : spike 2-3 cm, long, of 4-8 spikelets, which are 4-5.5 mm. long, each cluster naked 
at the base. 

On hills and plains, central Texas to Arizona. Spring and summer. Creeping Mesqihte. 

2. Hilaria mutica (Buckl, ) Benth. Stems rigid, 2-6 dm. tall, from rootstocks : leaf- 
blades erect, firm, 1 dm. long or less, 2-4 mm, wide : spike 4-6 cm. long : spikelets many, 
crowded, usually overlapping, 6-7 mm. long. 

On plains and prairies, Texas to Arizona. Also in Mexico. Summer and fall. Black Grama, 

17. NAZIA Adans. 

An annual grass, with flat leaf -blades and racemose or spike-like inflorescence, Spikelets 

articulated below the empty scales, 1-flowered, solitary, or in clusters of 3-5. Scales 2 or 3, 

the first small, or sometimes wanting, the second firm, with its nerves dorsally armed with 

hooked prickles, the third scale membranous, subtending a hyaline palet and a perfect 

flower. Stamens 3. Styles short, distinct. Stigmas moderately long, plumose. 

1. ^ Nazia alifena (Spreng.) Scribn. Tufted. Stems finally prostrate and rooting and 
branching at the lower nodes. 1-3 dm. tall : leaf -blades ciliate on the margin : spike 4-10 
cm. long ; spikelets about 2.5 mm. long. 

On dry hillsides, Texas to Arizona. Also in Central and South America, and the West Indies. 
Spring and fall. 









rOACEAE 



69 



18. LIMNTODEA L. 11. Dewey. 



Somewhat branched tufted grasses, with the stems usually decumbent at the base, nar- 
row flat leaf-blades, and narrow slender elongated contracted panicles. Spikelets 1-flow- 
^red, narrow, scattered on the panicle branches. Scales 3, the 2 outer empty, about equal 
in length, hispidulous or pilose, the nerves inconspicuous, the tliird scale scarcely shorter, 
thin, the apex shortly 2-toothed or 2-cleft, with an elongated slender geniculate or flexuous 
awn, which is a little twisted at the base, arising from between the teeth, the scale enclos- 
ing a somewhat shorter 2-keeled narrow hyaline palet and a perfect flower. Stamens 3. 
Styles short, distinct. Stigmas shortly pilose. [Thurberia Benth., not A. Gray.] 

1. Limnodea Arkans^na (Xutt. ) L. II. Dewey. Stems tufted, 2-4 dm. tall : leaf- 
sheaths glabrous or more or less hirsute ; blades erect, 3-12 cm. long, 2-8 mm. wide, more 
or less pubescent on both surfaces : panicle narrow, often partially included at the base, 
7-17 cm. long: spikelets 3.5-4 mm, long, the 2 outer scales tuberculate-hispidulous, the 
awn of the third scale geniculate, spiral at the base, 8-10 mm, long. [Thurberia Arkansana 
(Nutt.) Benth.] 

In dry soil, Florida, Arkansas and Texas. Spring.— A form known as L. Arkansana pildsa (Trin.) 
Nash {Sclerachne pilosa Trin.) is like the preceding, but the two outer scales are densely hirsute. It 
■occurs in Louisiana and Texas. 

19. REIMARIA Fluegge. 

Perennial grasses, usually diffusely branching, with ascending stems, and the inflores- 
cence composed of 2 or more secund racemes. Spikelets 1-flowered, awnless, acuminate, 
subsessile, alternately disposed in 2 rows on a narrow or somewliat dilated rachis. Scales 
2, the first empty, membranous, 3-5-nerved, acute, the second scarcely shorter and enclos- 
ing the slightly shorter palet and a perfect flower. Stamens 2. Styles distinct to the base. 
Stigmas long-plumose. 

1. Relmaria oligostdchya Munro. Smooth and glabrous. Stems compressed, 4-8 
dm. long : leaf-sheaths compressed ; blades erect or ascending, 5-15 cm. long, 2-4 mm. 
wide : racemes one-sided, in pairs at the summit of the stem, or sometimes with an addi- 
tional one a short distance below, 5-7 cm. long : spikelets broadly lanceolate, about 5 mm, 
long, aboiit twice as long as the rachis-internodes, the first scale 9-nerved, the four nerves 
on each side close together and rather distant from the midnerve. 

Along shores and in ditches, Florida. Summer. 



20. PASPALUM L. 

Usually perennial grasses with flat leaf-blades and an inflorescence composed of one or 
more unilateral racemes, arranged singly, in pairs, or in panicles. Spikelets 1-flowered, 
obtuse, or rarely short -acuminate, nearly sessile or short -pedicelled, alternately disposed, 
singly or in pairs, in 2 rows on one side of a narrow and usually winged rachis. Scales 3, 
rarely 4, the 2 outer, rarely 3, empty, membranous, usually equal in length, the flowering 
scales glabrous and shining, more or less convex, with its back turned toward the rachis, 
at length indurated, enfolding a shorter palet of similar texture and a perfect flower. Sta- 
mens 3. Styles distinct to the base, often elongated. Stigmas plumose. 

A. Rachis dilated, its broad margins membranous and at maturity inrolled 

on tliG SDikdGts 
Rachis long-acuminate, extending beyond the spikelets which are 1.5 

mm. long or less. 
Rachis acute, not extended ; spikelets about 2 mm. long or more. 2. P. manbranaceuni, 

B. Rachis more or less winged, rarely wingless, its margins not membranous 

nor enclosing the spikelets. 
a. Stems with l-several raceme-bearing naked branches from the upper- 
most sheath. 
1. Leaf-blades glabrous on the lower surface, or the midnerve some- 
times pubescent. 
♦Blades conspicuously ciliate. 

Uppermost sheath with the margins glabrous. 

Spikelets glabrous, or nearly so, rounded at the apex. 3. P. Uepharophyllum. 

Spikelets densely pubescent, obtusely apiculate at the apex. 4. P. propinquum. 
Uppermost sheath with the overlapping margin prominently cili- 

Spikelets orbicular, hence as broad as long, straw-color. 5. P. stramineum, 

Spikelets broadly obovate to oval, longer than broad, green. 
Spikelets densely pubescent, 2 mm. long, the leaves scat- 

tered along the stem. 6. P. Chapmanxx, 



1. P. mucronatum. 



70 



rOACEAE 



Spil^elets glabrous : 

2 mm. long : leaves scattered along the stem. 
1.5 ram. long : leaves crowded at the base of the stem : 
Upper surface of the blades glabrous ; marginal hairs 

less than 1 mm. long. 
Upper surface of the leaves pubescent with short 
hairs; marginal haii^ about 2 mm. long. 
**Blades naked on the margins, or rarely with a few scattered hairs. 
Racemes 1-3. 

Uppermost sheath pubescent on the overlapping margin. 
Leaf-blades lanceolate ; spikelets orbicular-obovate, the 

first and second scales strongly pubescent. 
Leaf-blades linear, rigid, long and narrow ; spikelets oval, 
the first scale sparingly pubescent. 
Uppermost sheath glabrous on the margin. 
Spikelets glabrous. 
Spikelets with the first scale pubescent. 

Leaf-blades linear, narrow, becoming involute; spike- 
lets elliptic. 
Leaf-blades linear-lanceolate, broad, flat ; spikelets 
broadly obovate. 
Racemes 6-12. 
2. Leaf-blades very pubescent on both surfaces. 

Stem long-hirsute below the raceme ; basal sheaths glubrous or 

nearly so. 
Stem glabrous throughout ; basal sheaths usually hirsute. 
Spikelets 1-1.5 mm. long. 

Stems slender ; blades narrow and scattered. 
Stems stout; blades broad, crowded at the base; pubescence 
very l©ng and copious. 
Spikelets 2-2.25 mm. long. 

Raceme on the main stem 1, or sometimes 2 together ; spike- 
lets glabrous ; leaf-blades not thick. 
Racemes on the main stem 2 or 3; spikelets usually more or 
less pubescent ; leaf-blades thick. 
t). Stems simple, no raceme-bearing branches from the uppermost sheath. 
1. Racemes 2-several, scattered, never in pairs. 
♦Stems tufted. 

fSpikelets rounded or obtuse at the apex, not ciliate on the mar- 
gins. 
gSpikelets convex on one side. 
Spikelets 3 mm. long or less. 

Spikelets singly disposed. 

Spikelets oval, J4 as thick as broad or more, the outer 

scales firm. 
Spikelets 2 mm. long, the flowering scale deep seal 

brown at maturity. 
Spikelets 2.5 mm. long, the flowering scale yellow- 
ish white at maturity. 
Leaf-sheaths glabrous. 

Blades short ; racemes usually 2 or 3. 
Blades elongated ; racemes usually 3-5. 
Leaf-sheaths hirsute, at least on the margins. 
Blades short, glabrous on the lower surface. 
Sheaths hirsute only on the mar^ns, or 
the basal ones sometimes sparingly so 
on the surface. 
Sheaths broad and much compressed, 
densely hirsute all over with very- 
long weak hairs. 
Blades elongated, more or less hirsute on 
both surfaces. 
Spikelets circular or nearly so, about 3^ as thick as 
broad, the outer scales very thin. ' 
Spikelets in pairs. 

Mature flowering scale white or yellowish. 
Spikelets 2 mm. long or less ; stems slender. 

Spikelets obovate, 1.5 mm. long, pubescent with 

spreading glandular-tipped hairs. 
Spikelets elliptic, 2 mm. long, sparsely pubes- 
cent with long appressed hairs. 
Spikelets 2.5-3 mm. long ; stems usually stout. 
Spikelets pubescent. 
Spikelets glabrous. 

Stems rooting at the lower nodes ; blades 

thin, long ; racemes 4-8. 
Stems not rooting at the lower nodes ; blades 
firm, short ; racemes 3, rarely 4. 
Mature flowering scale deep seal brown. 

Rachis broadly winged, wider than the spikelets 

which are about 2 mm. long. 
Rachis narrowly winged, much narrower than the 
spikelets which are 2.5-3 mm. long. 
Spikelets more than 3 mm. long. 

Racemes long and strictly erect, or short and ascending. 
Leaf-blades short ; racemes short and ascending. 
Sheaths glabrous or nearly so. 
Sheaths densely hirsute. 



7. P. ciliatlfolium. 



8. P. Keniuckieiise . 

9. P. longepedunculaium. 



10. P. Eggcrtii. 

11. P. rigid i folium 

12. P. epik. 



13. P. datum, 

14. P. latifolium, 

15. P. gracillimum 



16. P. pubescens. 



18. P. sctaceuni. 

19. P. villosissimnm. 



17. P. MuhlevhergiL 
20. P. dasyphyllum. 



21. P. scrohiculatum^ 



22. P. laeve. 

23. P. angustifolium 



24. P. australe. 



25. P. longipilum, 

26. P. praelonguni 

27. P. circulare. 



28. P. Simpsonii 

29. P. Blodgettil 

30. P. HaUiL - 



31. P. laeviglumis. 

32. P. geminum. 



33. P. Boscianum 

34. P. plicatulum. 



35. P difffynne. 

36. P. altissimiim. 



POACEAE 



71 



39. P. giganicuin, 

40. P. longlciUum, 

41. P. B uckleyamun , 



Leaf-blades elongated ; racemes long and erect. 

Sheaths glabrous, 37. P. glahmtum. 

Sheaths densely hirsute. 38. P. Floridanam, 

Racemes finally widely spreading. 

Sheaths glabrous ;" blades glabrous or ciliate with 
short hairs. 

Sheaths densely hirsute ; blades ciliate with long 
hairs. 
g§Spikelets flat, barely if at all convex on one side. 
Spikelets pubescent. 
Spikelets glabrous. 

Sheaths, excepting the exterior basal ones, glabrous, or 
the lower sometimes pubescent at the summit. 
Stems and sheaths much compressed, the former 
rather slender. 

Spikelets elliptic. 42. P. lividum. 

Spikelets orbicular or nearly so. 

Leaf-blades glabrous. 

Spikelets 2-2.5 mm. long. 43. P. prarcox. 

Spikelets 3 mm. long. 44. P. glahrrrimum. 

Leaf-blades hirsute : 

On the upper surface only : spikelets circular 

or nearly so. 45. P. tardiim. 

On both surfaces, strongly so on the lower : 

spikelets broadly obovate. 46. P. KearneyL 

Stems and sheaths not much compressed, the former 
stout. 
Sheaths densely hirsute. 48. P. Curtisianum, 

tfSpikelets acute, ciliate with very long hairs. 

Spikelets about 2.5 mm. long; racemes numerous (usually 10 

or more). 
Spikelets 3.5-4 mm. long ; racemes few to several (usually less 
than 8). 
**Stem single, from a long scaly rootstock. 

Scales of the rootstock appressed-pubescent : rachis of the ra- 
cemes not winged, the spikelets scattered. 51. P. hiftdiim. 
Scales of the rootstock glabrous : rachis of the racemes winged, 
the spikelets crowded. 
2. Racemes in pairs at the summit of the stem, rarely in 3's or with 
another raceme below. 
Stems tufted : racemes long and slender, the spikelets about 1.5 mm. 

long. 
Stems from long rootstocks : racemes short and stout, the spikelets 
exceeding 2 mm. long. 
Spikelets ovate, 2.5-3 mm. long, pubescent ; midnerve of the 

second scale present. 
Spikelets ovate-lanceolate, 3-4 mm. long, glabrous; midnerve 

of the rugose second scale suppressed. 55. P. vaginatum. 



47. P. amplum. 



49. P. Vaseyanum, 

50. P. dilatalum. 



62. P. solitarium. 



53. P. conjagatum. 



54. P. distichum. 



1. Faspalum mucronktum Muhl. Stems 1.5-8 dm. long, compressed, from a float- 
ing or creeping base, branched : leaf-sheaths loose or inflated, glabrous or hirsute ; blades 
8-30 cm. long, 6-25 mm. wide, acuminate, rough : racemes 20-100, scattered, or sometimes 
apparently whorled, 1-8 cm. long, slender, spreading, the rachis extending in an r 



nate point beyond the spikelets, the wings membranous and nearly enclosing the spikelets 

at maturity : spikelets singly disposed in two rows, elliptic, 1.2-1.5 mm. long and about 

0.6 mm. wide, pubescent. [P. fluitans Kunth.] 

In water, VirRinia to southern Illinois, Missouri, Florida and Texas. Also in tropical America. 
Fall. 

2. Faspalum membraniceum Walt. Stems sometimes 6-8 dm. long, compressed, 

creeping at the base, much branched : leaf -sheaths compressed, loose ; blades 3-8 cm. 
long, 4-6 mm. wide, smooth : racemes 3-7, erect, 2-3 cm. long, the rachis not extending 
beyond the spikelets, the Avings broad and nearly enclosing the spikelets at maturity : 
spikelets singly disposed in two rows, 2-2.3 mm. long and 1.3-1.5 mm. wide, oval, gla- 
brous. [P. Walterianum Schult.] 

In moist or wet soil, New Jersey and Delaware to southern Ohio, Florida and Texas. Fall. 

3. Faspalum blepharophyllum Nash. Stems tufted, 4-8 dm. tall : leaf-sheaths 
glabrous, even on the margins ; blades linear-lanceolate to lanceolate, glabrous on both 
surfaces, ciliate on the margins, 2.5 dm. long or less, 8-16 mm. w^ide : racemes usually 
single, commonly 6-8 cm. long, sometimes longer : spikelets in pairs, 2 mm. long and 
1.3-1.6 mm. wide, broadly obovate or oval, the first scale 3-nerved, usually pubescent with 
short hairs, the second scale 3-nerved, or sometimes 2-nerved by the suppression of the 
midnerve, glabrous. 

In sandy soil, Florida to Louisiana. Spring and summer. 

4. Paspalum proplaquum Nash. Stems tufted, 8-10 dm. tall : basal leaf-sheaths 
pubescent, the remaining ones glabrous ; blades glabrous on both surfaces, ciliate on the 
margins with stiff hairs, linear, erect or nearly so, 5-20 cm. long, 5-10 mm. wide : racemes 
rather slender, 8-12 cm. long, in I's or 2's : spikelets in pairs, on shorter pubescent pedi- 



72 



rOACEAE 



eels, oval, about 1.8 mm. long and 1.5 ram. wide, obtusely apiculate at the apex, the outer 
2 scales densely pubescent with short spreading ghinduhir-tippod liairs, the first scale 3- 
nerved, the second usually 2-nerved by the suppression of tlie midnerve. 

In dry sandy soil, peninsular Florida. Summer. 

5. Paspalum stramineum Xash. Foliage light yellowish green, tlie spikelets, and 
sometimes also theslieatlis, pale straw color. Stems tufted, 2-8 dm. tall : basal leaf-sheaths 
softly and densely pubescent, the remaining sheaths glal:>rous, excepting on the margins ; 
blades erect or nearly so, tirm, linear to lanceolate, long-ciliate on the margins, otherwise 
glabrous except usually on the midnerve beneath, 5-25 cm. long, 5-10 mm. wdde : racemes 
4-10 cm. long, on the main stem usually 2, rarely 1 or 3, single on the branches : spike- 
lets in pairs, on shorter pubescent pedicels, orbicular, 2 mm. in diameter, the first scale 
3-nerved, pubescent witli sliort spreading glandular-tipi^ed hairs, the second scale glabrous 
or nearly so, 2-nerved, tlie midnerve suppressed. 

In sandy places and fields, Nebraska, Kansas and the Indian Territory. Summer and fall. 

6. Paspalum Chapmanii Nash. Stems tufted, 8-10 dm. tall : basal leaf-sheatlis 
pubescent, the remaining ones glabrous except on the margins ; l)lades glabrous on both 
surfaces, the margins ciliate, lanceolate to linear-lanceolate, rather thin, 7-20 cm. long, 
7-14 mm. wide : racemes 10-12 cm. long, rather slender, usually in 2's on the main stem, 
single on the branches : spikelets in pairs on shorter pubescent pedicels, oval, 2.2 mm. long 
and about 1.8 mm. broad, the 2 outer scales densely pubescent with short spreading gland- 
ular-tipped hairs, 3-nerved, or the second often 2-nervedby the suppression of the mid verve. 

In dry sandy soil, Florida. Summer. 

7. Paspalum ciliatifolium Michx. Stems tufted, erect, 4-8 dm. tall, smooth and 
glabrous : leaf-sheaths ciliate on the overlapping margin, otherwise glabrous ; blades 5-25 
cm. long, 6-15 mm. wide, smooth and glabrous on both surfaces, the margins conspicuously 
ciliate with long hairs: racemes single, or sometimes in 2\s, 5-11 cm. long: spikelets in 
pairs, 1.8-2.1 mm. long and 1.5-1.8 mm. broad, oval to broadly obovate, the 2 outer 
scales 3-nerved or the second one rarely 2-nerved by the suppression of the midnerve, 
both the scales glabrous. 

In sandy or rocky soil, District of Columbia to Alabama and Mississippi. Summer and fall. 

8. Paspalum Kentuckiense Nash. Stems tufted, 2-5 dm. tall, slender : leaf-sheaths 
ciliate on the overlapping margin, otherwise glabrous ; blades erect, lanceolate, 6 cm. long 
or less, 4-10 ram. wide, glabrous on both surfaces, ciliate on the margins with hairs less 
than 1 mm. long: racemes single or in pairs, 2-5 cm. long : spikelets about l.G mm. long 
and about 1.3 mm. wide, the scales glabrous, the first scale 3-nerved, the second one usu- 
ally 2-nerved by the suppression of the midnerve. 

In dry soil, Kentucky and Tennessee. Summer. 

9. Paspalum longepedunculatum Le Conte. Stems tufted, 2.5-8 dm. tall, smooth 
and glabrous : leaf-sheaths glabrous excepting on the pilose margins, crowded towards the 
base of the stem : blades 2.5-9 cm. long, rarely a little longer, 4-9 mm. broad, smooth and 
glabrous below, pubescent above with short appressed hairs, conspicuously ciliate on the 

, the hairs about 2 mm. long : racemes in I's or 2's, 2.5-8 cm. long : spikelets in 



pairs, 1.5-1.8 mm. long, 1-1.2 mm. wide, broadly obovate, glabrous, the first scale 3-nerved, 
the second 2-nerved by the suppression of the midnerve which is rarely present. 

In sandy or rocky soil, Georgia and Florida. Summer and fall. 

10. Paspalum Eggertii Nash. Stems tufted, 3-5 dm. tall: basal leaf-sheaths pubes- 
cent, the remainder ciliate on the overlapping margin but otherwise glabrous ; blades lan- 
ceolate, glabrous on both surfaces and on the margins, 10 cm. long or less, 4-8 mm, wide : 
racemes single or in pairs, 4-6 cm. long : spikelets in pairs, a little exceeding 2 mm. long 
and about 1.5 mm. wide, oval, the first scale strongly pubescent with short spreading hairs, 

3-nerved, the second scale usually 2-nerved by the suppression of the midnerve, sparingly 
pubescent with similar hairs. 

On sandy ridges, Arkansas. Fall. 

11. Paspalum rigidifolium Nash, Stems tufted, erect, 3-8 dm. tall, smooth and 
glabrous : basal leaf-sheaths softly pilose with rather long spreading hairs, the remaining 
ones glabrous ; blades erect or ascending, rigid, linear, glabrous, 7-20 cm. long, 3-7 mm. 
wide : racemes single, or rarely in 2's, 6-13 cm. long : spikelets in pairs, on shorter glabrous 
or nearly glabrous pedicels, 2.3-2.5 mm. long, 1.7-2 mm. wide, oval or broadly obovate, 
the first scale more or less pubescent wuth spreading hairs, 5-nerved, the second scale 
glabrous, 5-nerved, or sometimes 4-nerved by the suppression of the midnerve. 

In dry sandy soil, peninsular Florida. Spring. 

12. Paspalum 6pile Nash. Whole plant glabrous. Stems 6-8 dm. tall : leaf- 
blades thick, tirm, linear-lanceolate, 2 dm. long or less, 7-10 mm. wide : racemes single or 



rOACEAE 



73 



in pairs, 6-10 cm. long: spikelets in pairs, 2 mm. long and about 1,5 mm. wide, broadly 
obovate, tlie first scale 3-nerved, the second one generally 2-nerved by the suppression of the 
midnerve. 

In sand, Key AVest, Florida. Spring to fall. 

13. Paspalum elatum L, C. Rich. Stems 6-8 dm. tall : leaf-sheaths glabrous ; 
blades 3 dm. long or less, 2-6 mm, wide, densely pubescent with long liairs above at the very 
base, otherwise glabrous : racemes in 3' s, 10-13 cm. long: spikelets on hispidulous pedicels, 
elliptic, about 2.2 mm. long and 1.3 mm. wide, the 2 outer scales 3-nerved, the first scale 
pubescent Avith long appressed liairs, the second one glabrous. 

In sandy soil, Key West, Florida. Also in tropical America. Spring to fall. 

14. Paspalum latifolium Le Conte. Stems tufted, 6-8 dm. tall : leaf-sheaths smooth 
and glabrous, or the basal ones a little pubescent; blades 1.5-3 dm, long, or the upper- 
most often shorter, 1-2 cm. wide, rather thin, lanceolate to linear-lanceolate, ghibrous, or 
some of them occasionally with a few scattered hairs on the margins near the base : racemes 
on the main stem usually in pairs, rarely single, those on the brandies single, 6-12 cm. 
long : spikelets in pairs, on shorter puberulent pedicels, about 2 mm. long and 1.5-1.7 mm. 
wide, broadly obovate, the first scale 3-nerved, pubescent with short spreading hairs, the 
second scale 3-nerved, or rarely 5-nerved, glabrous. 

In dry usually shady places, Georgia and Florida. Spring and summer. 

15. Paspalum gracillimum Nash. Stems slender, 4-6 dm, tall : leaf-sheatlis smooth 
and glabrous : blades (the upper ones) 1.6 dm. long or less, 2-7 mm. wide, flat, a ring of 
long hairs just above the ligule, otherwise glabrous : racemes 6-10, usually alternate, 
widely spreading, slender, 3-7 cm. long : spikelets in pairs, obovate, 1.4 mm. long and 0.9 
mm. wide, the 2 outer scales 3-nerved, the first scale pubescent with short glandular-tipped 
liairs, the second scale glabrous, the third scale about i as thick as broad. 

In sandy soil, Key West, Florida, Spring to fall. 

16. Paspalum pub^scens Muhl. Stems tufted, 4-8 dm. tall, long-hirsute below the 
racemes : leaf -sheaths glabrous, or sometimes pubescent on the margins or toward the apex, 
the basal ones sometimes pubescent all over ; blades 4-23 cm. long, 3-6 mm. wide, rarely 
broader, densely pubescent on both surfaces with long spreading rather stiff hairs arising 
from papillae, if ciliate on the margins the hairs short : racemes usually 1, rarely 2 on the 
main stem, generally straight, or sometimes a little curved, 6-12 cm. long, rarely sliorter : 
spikelets in pairs, glabrous, on shorter puberulent pedicels, about 2 mm. long and 1.5-1.8 
mm. wide, broadly obovate, the 2 outer scales 3-nerved, or the second 2-nerved by the sup- 
pression of the midnerve, the flowering scale triangular in cross-section, the angles rounded, 
about two-thirds as thick as broad. 

In fields, New York and New Jersey to Pennsylvania, District of Columbia and Tennessee. Sum- 
mer and fall. 

17. Paspalum Muhlenb^rgll Nash. Stems tufted, at first erect, finally reclining, 
4-8 dm. tall, smooth and glabrous ; leaf-sheaths generally pubescent all over with long 
hairs or sometimes only on the margins; blades 0.5-2 dm. long, rarely longer, usually 
7-11 mm. Avide, or sometimes narrower, ciliate on the margins with usually long hairs, 
more or less pubescent on both surfaces with long hairs : racemes in I's or 2' s, straight or 
curved, 5-10 cm. long : spikelets in pairs, glabrous, on shorter puberulent pedicels, about 
2 mm. long and 1.8 mm. wide, oval or broadly obovate, the 2 outer scales 3-nerved, or the 
second rarely 2-nerved by the suppression of the midnerve, the flowering scale triangular 
in cross-section, the angles rounded, about J as thick as broad. 

In fields or in sandy or stony ground, Massachusetts to Missouri and tlie Indian Territory, South 
Carolina, Georgia and Mississippi. Late summer and fall. 

18. Paspalum setAceum Michx. Stems tufted, slender, 2-7 dm. tall : basal leaf- 
sheaths densely pubescent with long hairs, the upper ones only' on the margins ; blades 
3-14 cm. long, rarely somewhat longer, usually 2.5-5 mm. wide, sometimes a little 
broader, linear, strict and erect or ascending, densely pubescent on both surfaces with long 

hairs : ranpnip« sinVlp. slpnder. 




8in 



wide, broadly obovate, the first scale 3-nerved, "pubescent with spreading glandular-tipped 
hairs, the second scale 2-nerved, the midnerve rarely, if ever, present, glabrous or occasion- 



ally pubescent. 

In dry sandy soil, southeastern Xew York to Florida, west to Mississippi. Summer and fall. 

19. Paspalum villosissimum Na-sh. Plant yellowish gray-green. Stems tufted, 
erect, 4-10 dm. tall : leaf-sheaths crowded at the base of the stem, very densely pubescent, 
as well as both surfaces of the bladas, with very long white spreading hairs ; blades erect 
or ascending, thick, lanceolate, 2 dm. long or less, 6-10 mm. broad : racemes single or in 



74 



POACEAE 



pairs, 5-9 cm. long : spikelets in paii*s, on shorter pnbernlent pedicels, abont 1.8 mm. long 
and about 1.5 mm, wide, broadly obovate, the 2 outer scales densely pubescent with spread- 
ing glandular-tipped hairs, the first scale 3-nerved, the second 2-nerved, or the midnerve 
very nirely present. 

In dry sandy soil, peninsular Florida. Summer. 

20. Paspalum dasyphyllum Ell. Plant yellowish green. Stems tufted, stout, 2-6 
dm. tall ; leaf-sheaths, as well as both surfaces of the blades, densely pubescent with long 
jellowish spreading hairs ; blades erect or ascending, thick, lanceolate, 2 dm, long or less, 
usually 1-2 cm. broad, sometimes a little narrower: racemes on the main stem in 2^s or 
3' 8, those on the branches single, 4-10 cm. long : spikelets in pairs, on shorter puberulent 
pedicels, 2-2.2 mm. long and about 1.8 mm. wide, broadly obovate, the first scale usually 
more or less pubescent with spreading glandular-tipped hairs, 3-nerved, the second scale 
glabrous, usually 2-nerved or sometimes 3-nerved. 

In dry usually sandy places, South Carolina to Florida ; also in Missouri. Summer. 

21. Paspalum acrobiculktum L. Glabrous. Stems densely tufted, 2-6 dm. tall : 
leaf -blades erect, flat, 1 dm. long or less, 2-5 mm. wide, those on the innovations longer : 
racemes 2-5, erect or nearly so, 2-4 cm. long : spikelets singly disposed, oval, about 2 mm. 
long and 1.5-1-75 mm. wide, glabrous, the outer scales 5-nerved, the lateral nerves ap- 
proximate and distant from the midnerve, the third scale deep seal brown when mature, 
scrobiculate. 

In sandy soil, Florida. Also in tropical countries. Summer and fall. Ditch Millet. 

22. Paspalum la^ve Michx. Stems tufted, 3-6 dm. tall : leaf -sheaths compressed, 
glabrous; blades short, those on the stem usually less than 1.5 dm. long, 5-8 mm. wide, 
pubescent above near the base : racemes 2 or 3, spreading, 4-8 cm. long : spikelets singly 
disposed, glabrous, oval, 2.5-3 mm. long, 2-2.5 mm. wide, the 2 outer scales 3-nerved. 

In fields, District of Columbia to Kentucky, Georgia, Arkansas and Texas. Summer. 

23. Paspalum angustifolfum Le Conte. Stems tufted, 6-12 dm. tall : leaf-sheaths 
compressed, glabrous ; blades long, the larger 2-4 dm. long, less than 1 cm. wide, gla- 
brous, or the upper surface sometimes sparingly hirsute near the base : racemes 3-5, spread- 
ing, usually 6-10 cm. long, sometimes shorter: spikelets singly disposed, oval, 3-3.5 mm. 
long and about 2.5 mm. wide, glabrous, the 2 outer scales 3-nerved. 

In fields, District of Columbia to northern Florida, Louisiana, Kansas and Missouri. Summer 
and fall. 

24. Paspalum auatrale Nash, Stems tufted, 4-7 dm. tall : leaf-sheaths usually hir- 
sute only on the margins ; blades erect, short, generally 1.5 dm. long or less, 5-10 mm. 
wide, strongly ribbed, rather thick, firm, glabrous beneath or nearly so, hirsute above : 
racemes 2-5, usually 2 or 3, finally spreading, commonly 5 cm. long or less, sometimes 
longer : spikelets singly disposed, oval, 2. 7-3 mm. long and about 2 mm. wide, the 2 outer 
scales 3-nerved, glabrous. 

On grassy flats and banks, Virginia to Florida and Alabama. Summer and fall. 

25. Paspalum longipilmn Nash. Stems tufted, compressed : leaf -sheaths much com* 
pressed, keeled, the lower ones strongly hirsute with very long hairs : blades erect, firm? 
stiff, folded when dry, 2 dm. long or less, 6-12 mm. wide, glabrous beneath, densely hir- 
sute above with very long hairs : i-acemes 2 or 3, spreading or ascending, usually 4—6 cm. 
long, sometimes longer : spikelets singly disposed, oval, about 3 mm. long and a little ex- 
ceeding 2 mm. broad, the 2 outer scales glabrous, 5-nerved, the lateral nerves close together 
and near the margin. 

In moist or wet soil, i)eninsular Florida. Spring and summer, 

26. Paspalum praeldngum Nash. Stems tufted, 5-10 dm. tall : leaf-sheaths usually 
hirsute all over; blades long, usually exceeding 1.5 dm., sometimes 3 dm. long, 5-10 mm. 
wide, thin, lax, hirsute on both surfaces : racemes 2-4, usually 3 or 4, finally spreading, 
5-10 cm. long: spikelets singly disposed, oval, 2.5-2.8 mm. long and about 2 mm. wide, 
the 2 outer scales 3-nerved, glabrous. 

In moist or dry soil, District of Columbia to Georgia, Alabama and Missouri, Summer and fall. 

27. Paspalum circiilkre Nash. Stei;is tufted, 4-8 dm. tall : leaf-sheaths hirsute 
with long hairs, compressed ; blades 2 dm. long or less, 5-8 mm. Avide, glabrous beneath 
or hirsute along the midnerve, the upper surface hirsute with long hairs : racemes 2-4, 
spreading or ascending, 4-6 cm. long : spikelets singly disposed, glabrous, orbicular, about 
2.5 mm. in diameter, the 2 outer scales thin, finely but distinctly striate. 

In fields and meadows, New York to North Carolina ; also in Missouri Summer and fall. 

28. Paspalum Simpsonii Nash. Stems tufted, slender, 4-8 dm. tall : basal leaf- 
sheaths hirsute, the rest glabrous; blades lanceolate, 4-10 cm. long, 3-10 mm. wide, gla- 
brous on both surfaces, ciliate on the margins below the middle : racemes 3-5, spreading, 



POACEAE 



75 



2-7 cm. long: spikelets in paii-s, obovatCj 1.3-1.5 mm. long and about 0.8 mm. broad, the 
2 outer scales 3-nerved, densely pubescent with short glandular-tipped hairs. 
In rocky pine woods, Xo-namc Key and Key West, Florida. Spring and summer. 

29. Paspalum Blodg^ttii Chapm. Smooth and glabrous. Stems densely tufted, 
slender, 3-6 dm. tall : leaf-blades 5-15 cm. long, 3-7 mm. wide, narrowed at both ends : 
racemes erect, 2-6, 1.5-6 cm. long, slender, the rachis flat, winged, about 0.5 mm. broad, 
about 2 as wide as the spikelets : spikelets in pairs, 1.5-2 mm. long, about 1 mm. broad, 
elliptic to obovate, the 2 outer scales papillose-pubescent with appressed hairs, 3-nerved. 

On coral soil or shell mounds, Florida. Also in Cuba. Spring and fall. 

30 Paspalum Hdllii Vasey & Scribn. Stems 4-10 dm. long, finally prostrate and 
rooting toward the base, the nodes pubescent : leaf-sheaths more or less hirsute on one 
margin, the exterior basal ones hirsute all over ; blades 3 dm. long or less, 1-1.5 cm. wide, 
glabrous on both surfaces : racemes 2-4, usually ascending, the lower ones 5-10 cm. long : 
spikelets in pairs, broadly obovate, 2.5-3 mm. long and about 2 mm. broad, the 2 outer 
scales 3-nerved, the first scale strongly hirsute, the second one glabrous. 

In moist soil, Louisiana and Texas. Spring. 

31. Paspalum laeviglumis Scribn. Stems 5-15 dm. long, finally prostrate and 
rooting toward the base, the nodes pubescent : sheaths more or less hirsute on one margin, 
otherwise glabrous ; leaf -blades 1-4 dm. long, 1-2 cm. wide, glabrous on both surfaces : 
racemes 4-7, spreading or ascending, the lower ones usually 5-10 cm. long: spikelets in 
pairs, oval to broadly obovate, 2.7-3 mm. long, 1.8-2 mm. broad, glabrous, the first scale 
3-5-nerved, the second scale 5-7 -nerved. 

In moist places, Tennessee to the Indian Territory, Mississippi and Texas. Summer and fall. 

32. Paspalum g^minum Nash. Stems 5-7 dm. tall : leaf-sheaths compressed, keeled, 
glabrous, or the basal ones pubescent; blades erect, firm, thick, 2 dm. long or less, 6-10 

mm. wide, glabrous beneath, hirsute above near the base with long hairs : racemes about 3, 
sometimes more, spreading or ascending, 4-6 cm. long : spikelets in pairs, elliptic, 3-3.3 mm. 
long and about 2 mm. wide, glabrous, the 2 outer scales 3-nerved. 

In fields and orchards, Florida, Spring and summer. 

33. Paspalum Bosci^num Fluegge. Stems 5-12 dm. long, compressed, finally 
branched, often decumbent at the base and rooting at the lower nodes : leaf-sheaths com- 
pressed, smooth and glabrous, or the basal ones papillose-hirsute; blades 4-30 cm. long, 
3-10 mm. wide, smooth or roughish, papillose-hirsute above near the base : racemes 2-13, 
spreading or ascending, 4-9 cm. long, the rachis straight, 2-2,6 mm. wide, broadly 
winged : spikelets in pairs and often so crowded as to appear in four rows, frequently red- 
brown, broadly obovate, 2-2.3 mm. long, 1.5-1.8 mm. broad, the 2 outer scales smooth and 
glabrous, the first 5-nerved, the second 3-nerved, the flowering scale faintly pitted in close 
longitudinal lines, deep brown at maturity. [P. purpurascens Ell.] 

In meadows and moist places, North Carolina to Florida and Mississippi. Summer and fall. 

34. Paspalum plicktulum Michx. Stems tufted, flattened, 4-8 dm, tall : leaf- 
sheaths compressed, smooth and glabrous ; blades usually folded, at least when dry, more 
or less long-hairy above, erect, rather stiff, 2 dm. long or less, 2-5 mm. wide : racemes 
3-7, rarely fewer, spreading or ascending, 3-7 cm. long : spikelets brown at maturity, 
elliptic, 2.5-3 mm. long and about 1.8 mm. wide, the first scale 5-nerved, the lateral 
nerves approximate, more or less pubescent with appressed hairs, the second scale glabrous, 
3-nerved, the margins usually more or less transversely plicate, the third scale seal-brown 
at maturity. 

In dry, usually sandv soil, Georgia and Florida to Texas. Also in Mexico, South America and the 
West Indies. Spring to fall. 

35. Paspalum diffdrme Le Conte. Stems 5-10 dm. tall, rather stout, leafy below, 
not tufted : leaf-sheaths somewhat compressed, the external basal ones, as well as some- 
times the summit of the others, papillose-hirsute ; blades erect or nearly so, commonly 
less than 1.5 dm, long, 6-10 mm. wide, flat, glabrous or hirsute above and sometimes more 
or less so below : racemes 2 or 3, ascending, short, commonly 4-6 cm. long : spikelets usu- 
ally singly disposed, or rarely some of the central ones in pairs, 3-3.5 mm. long and about 
2. 6 mm. broad, the 2 outer scales 3-nerved, glabrous. 

In low grounds, Georgia and Florida. Summer. 

36. Paspalum altissimum LeConte. Stems usually 5-8 dm. tall, rarely taller, slen- 
der: leaf-sheaths hirsute with rather short hairs; blades short-hirsute on both surfaces, 
commonly Jess than 2 dm. long, 3-6 mm. wide : racemes generally in pairs, 5-8 cm. long, 
ascending : spikelets usually singly disposed, sometimes in pairs, about 3.5 mm. long and 
2.5 mm. wide, the 2 outer scales glabrous, 3-nen'ed. 

In dry pine lands, Alabama and Mississippi. Fall. 



7G 



POACEAE 



37. Paspalum glabiatum (Engelm. )C. Mohr. Whole plant often glaucous. Stems 
usually 1-2 in. tall, stout, leafy : leaf-sheatlis glabrous, or sometimes sparingly pubescent, 
the external basal ones sometimes hirsute ; blades glabrous on the lower surface, the upper 
surface glabrous or more or less hirsute, tlie lower blades 3-7 dm. long, 6-15 mm. wide: 
racemes usually 3-6, sometimes 2, erect or nearly so, the lower ones commonly 1-1.5 dm. 
long, occasionally shorter or longer: spikelets singly disposed or in pairs, 3.5-4.5 mm. 
long, 2.75-3.5 mm. Avide, the 2 outer scales glabrous, 3-nerved. ' 

In low ground, Maryland to Kansas, Georgia and Texas. Summer and fall. 

38. Paspalum Floridanum Miclix. Stems 9-12 dm. tall, rather stout, leafy : leaf- 
sheaths densely liirsute with long hail's ; blades densely hirsute above and usually also on 
the lower surface, the lower ones 3-6 dm. long, 6-10 mm. wide : racemes commonly 2 or 
3, rarely 4, erect, the lower ones usually 8-12 cm. long : spikelets usually singly disposed, 
3.5-4 mm. long, 2.5-3 mm. wide, the 2 outer scales 3-nerved, glabrous. 

In low ground, South Carolina to Florida, west to Texas. Summer and fall. 

39. Paspalum gigant^uxn Baldw. Stems tufted, 1-1.5 m. tall, stout: leaf-sheaths 
glabrous ; blades erect, glabrous on both surfaces, if ciliate on the margins the hairs short, 
the lower leaves 2-3 dm. long, 1.5-2 cm. Avide : racemes 3-5, finally widely spreading, 
1-1.5 dm. long: spikelets in pairs, about 3.25 mm, long and 2.5 mm. wide, the 2 outer 
scales glabrous, 3-nerved. 

In ditches and swamps, Florida. Summer. 

40. Paspalum longicilium Nash. Stems tufted, ascending, stout, 6-12 dm. tall : 
lower leaf-sheaths densely papillose-hirsute with long shaggy hairs ; blades glabrous on both 
surfaces, the margins ciliate with very long hairs, the lower blades 2-4 dm. long, 1-2 cm. 
wide : racemes ascending, the lower ones 8-17 cm. long : spikelets usually singly disposed, 
3-3.3 ram. long and 2-2.3 mm. wide, the 2 outer scales glabrous, 3-nerved. 

In clay soil in ditches, central peninsular Florida. Summer. 

41. Paspalum Buckleyanum Vasey. Stems erect, 6-8 dm. tall: leaf-sheaths 
smooth and glabrous ; blades 4-20 cm. long, 2-4 mm. wide, rough above, smooth beneath : 
racemes erect, 2-4, 5-7 cm. long, the racliis straight, broadly winged, 1.5-2 mm. wide: 
spikelets in pairs, often so crowded as to appear as if in 4 rows, 3 mm. long, about 1.5 mm. 
broad, elliptic, the 2 outer scales 3-nerved, densely appressed-pubescent, the flowering scale 
yellowish at maturity, faintly pitted in fine longitudinal lines. 

pn low grounds, Texas. Summer and fall. 

42. Paspalum lividum Trin. Stems 6-10 dm. tall : leaf-sheaths compressed, 
keeled, smooth, glabrous, except on the margins ; blades 3 dm. long or less, 3-5 mm. wide 
more or less pubescent on the upper surface : racemes 3-7, erect or ascending, 2^5-5 cm. 
long, the rachis often setiferous on the margins : spikelets bright green, in pairs, elliptic, 
acute or acutish, about 2.5 mm. long and 1.5 mm. wide, the 2 outer scales 3-nerved, gla- • 
brous, the third scale yellowish white, only slightly convex in cross-section. 

In wet places, Texas. Also in Mexico and South America. Summer. 

43. Paspalum pra^coz Walt. Stems tufted, compressed, 6-12 dm. tall : leaf -sheaths 
compressed, the lower ones purple, the exterior basal ones hirsute, the remainder glabrous ; 
blades 2 dm. long or less, 4-6 mm. wide, glabrous : racemes usually 4 6, rarely more or 
fewer, ascending, 2-5 cm. long : spikelets in pairs, lenticular, nearly flat on the inner side, 
yellowish green, orbicular to oval, 2.2-2.6 mm. long, 1.8-2.2 mm. wide, the 2 outer 
scales glabrous, 3-nerved, the third scale striately roughened with conspicuous papillae. 

In moist or Avet places, South Carolina to Florida and Texas. In spring and early summer ; some- 
times also in the late fall. 

44. Paspalum glab6rrlmum Xash. Glabrous. Stems single, about 1 m. tall, erect, 
compressed : leaf-sheaths compressed ; blades erect, long-acuminate, the larger 3-4 dm. 
long, 5-8 mm. wide, the upper blade very short or wanting : racemes 3 or 4, ascending, the 
lower 4-7 cm. long : spikelets nearly circular, barely if at all convex on one side, 3 mm. 
long, light green, the 2 outer scales 3-nerved. 

In low pine lands, southern i)eninsular Florida. Summer. 

45. Paspalmn tdrdum Nash. Stems not tufted, compressed, usually 6-13 dm. tall : 
leaf-sheaths compressed, the outer basal ones densely papillose-hirsute with long hairs, the 
remainder similarly pubescent with very long hairs at the apex ; blades 1.5-2.5 dm. long, 
3-6 ram. wide, glabrous beneatfi, hirsute above toward the base, especially near the base 
where the hairs are very dense and long : racemes usually 3 or 4, sometimes only 2, spread- 
ing or ascending, commonly 3-6 cm. long, sometimes shorter : spikelets singly or in pairs, 
orbicular or nearly so, 2.2-2.5 mm. in diameter, the 2 outer scales 3-nerved, glabrous, the 
third scale striately roughened with conspicuous papillae. 

In wet ground, Florida to Mississippi. Summer and fall. 



J 



POACEAE 



7/ 



46. Paspalum Kearney i Nash. Stems single, slender, 8-10 dm. tall, compressed : 
leaf-slieatlis compressed, the external basal ones hii-sute, as well as sometimes tlie summit 
of some of the others ; blades erect, elongated, densely hii-sute on both surfaces, long- 
acuminate, the lower ones 2-3 dm. long, 4-5 mm. wide : racemes about 3, spreading, 3-4 
cm. long : spikelets broadly obovate, 2.8 mm. long and about 2 mm. wide, barely if at all 
convex on one side, light green, the 2 outer scales 3-nerved. 

In dry soil, Mississippi. Fall. 

47. Paspalum dmplum Xash. Stems tufted, stout, 1-1.5 m. tall, round or but 
little compressed : leaf-sheaths a little flattened, the outer basal ones hirsute below, the 
remainder glabrous, excepting a tuft of long hairs at the aj^ex ; blades 2-5 dm. long, 5-10 
mm. wide, glabrous beneath, pubescent above with short appressed hairs and near the base 
with very long ones : racemes usually 6-8, erect or ascending, the lower ones commonly 
8-15 cm. long: spikelets orbicular to oval, about 3 mm. long and 2.5-3 mm. ^wide, tlie 
third scale strongly roughened with conspicuous papillae. 

In wet ground, Florida to Mississippi. Summer, 

48. Paspalum Curtisi^num Steud. Stems stout, 8-10 dm. tall : leaf-sheaths 
densely papillose-hirsute with long ascending hairs ; blades 1.5-4 dm. long, 5-7 mm. wide, 
strongly papillose-hirsute, especially above, wdth long hairs : racemes 5»-10, finally spread- 
ing, 3-8 cm. long : spikelets single or in pairs, lenticular, 2.5-3 mm. in diameter* the 
2 outer scales glabrous, 3-nerved, the third scale striately roughened with conspicuous 
papillae. 

In wet places, South Carolina to Florida and Mississippi. Summer. 

49. Paspalum Vaseyinum Scribn. Stems 1-1.5 m. tall, stout: lower leaf-sheaths 
densely papillose-hispid with ascending hairs ; blades 4 dm. long or less, 8-12 mm. M'ide, 
hirsute above at the very base, otherwise glabrous : racemes erect, 10-20, the lower 8-12 
cm. long : spikelets in pairs, acute, 2.3-2.5 mm. long and about 1.4 mm. wide, the 2 outer 
scales 3-nerved, acute, pilose on the margins with very long hairs, the surface, especially 
that of the first scale, pubescent with shorter hairs. 

In fields, Alabama to Texas. Summer and fall. 

50. Paspalum dilat^tum Poir. Smooth and glabrous. Stems 5-17 dm. tall, some- 
what compressed : leaf-blades 3 dm. long or less, 3-12 mm. wide : racemes 5-10 cm. long, 
erect or ascending, the rachis broadly winged, 1.2-1.5 mm. wide, straight: spikelets in 
pairs, so densely crowded as to appear as if in 4 rows, 3-3.3 nmi. long, 2-2.2 mm. broad, 
nearly orbicular, apiculate, much compressed dorsally, the 2 outer scales 5-7 -nerved, the 
first scale ciliate on the margins with very long lax hairs, the second sparingly ciliate with 



much shorter hairs, the flowering scale white at maturity, orbicular. 

In meadows and moist places, Georgia and Florida to Louisiana. Summer and fall. 

51. Paspalum bffidum (A. Bertol. ) Nash. Glaucous. Stems 7-13 dm. tall, single, 
from a stout scaly rootstock, its scales strongly appressed-hirsute : leaves mostly at the 
base of the stem ; sheaths, at least the external basal ones, papillose-hii-sute ; blades 3 dm. 
long or less, generally 5-10 mm. wide, narrowed at both ends, glabrous or but sparingly 
hirsute beneath, strongly hirsute above toward the base : racemes usually 2 or 3, sometimes 
more or only 1, 7-15 cm. long, erect, the rachis triangular, slender, the lateral margins 
not winged: spikelets in rather distant pairs, oval, 3.5-4 mm. long and about 2.5 mm. 
broad ; scales usually 3 (sometimes 4 and the first one minute), the first scale 7-nerved, the 
second one 5-nerved. [P. racemidosum Isutt.] 

In dry pine lands or on wooded hillsides, North Carolina to Florida and Louisiana, Fall. 

52. Paspalum solitarium Nash. Eootstock long and stout, scaly, the scales gla- 
brous. Stems single, rigid, 6-10 dm. tall (rarely shorter) : leaf-sheaths sometimes pubes- 
cent on the exterior margin ; blades elongated, stiflT, the larger ones often 3-6 dm. long, 
involute at least when dry, long-acuminate, glabrous: raceme 1, or rarely 2 rax^emes, 1-2 
dm. long, erect : spikelets crowded in pairs on hispid pedicels, glabrous, 3 mm. long and 
about 1 5 mm. wide, elliptic, the 3 outer scales 3-nerved. [P. monostachyum Vasey, not 

Walp. ] 

In wet soil, southern Florida and Texas. Fall. 

53. Paspalum conjugktiun Berg. Smooth and glabrous. Stems compressed, 2-9 
dm. tali finally decumbent at the base and rooting at the lower nodes : leaf-blades 4-16 
cm." long 4-12' mm. wide : racemes in pairs, slender, often curved, spreading or ascending, 
5-12 cm long the rachis straight, or flexuous toward the apex, 0.6-0.8 mm. broad: spike- 
lets crowded, much compressed dorsally, singly disposed, 1.5 mm. long, 1-1.2 mm. broad, 
apiculate the 2 outer scales 2-nerved, the nerves marginal the first scale ciliate on the 
margins with very long lax hairs, the third scale smooth, white. 

In wet places. Louisiana and Texas. Common in all tropical countries. Summer. 



78 



POACEAE 



54. Faspalum distlchum L. Stems 1-6 dm. tall, from a long stout rootstock : 
leaf-sheaths compressed, keeled, usually crowded and overlapping, especially at the base 
and on the innovations, glabrous, or more or less hairy on the margins ; blades com- 
monly less than 1 dm. long, 3-6 mm. wide, generally glabrous : racemes terminal, in pairs, 
ascending, 2-5 cm. long : spikelets singly disposed, ovate, 2.5-3 mm. long, acute, the 
2 outer scales firm, 5-nerved, rarely 7-nerved, the first scale glabrous, the second appressed- 
pubescent, the third apiculate, strongly pubescent at the apex. 

In sandy soil, on the seashore or along rivers. Virginia to Missouri, Florida and Texas, and on the 
Pacific coast. Also in tropical America. Summer and fall. 

55. Paspalum vaginktum Sw. Stems 2-6 dm, tall, from a long stout rootstock : 
leaf-sheaths compressed, keeled, usually crowded and overlapping, at least at the base and 
on the innovations, glabrous ; blades folded, or involute when dry, 1.5 dm. long or less, 
2-4 mm. wide, glabrous, or sparingly hairy above at the very base : racemes terminal, usu- 
ally in pairSj rarely more or but a single one, erect or ascending, 3-7 cm. long : spikelets 
singly disposed, ovate-lanceolate, acute, 3-4 mm. long, the 2 outer scales glabrous, thin, 
the first scale 4-nerved, the lateral nerves approximate at the margin, the midnerve sup- 
pressed, the second scale 5-nerved, the lateral nerves rather near together, the third scale 
glabrous at the apex or with 2 or 3 hairs. 

Along the seashore, Plorida to Texas. Also in the AVest Indies. Summer and fall. 

21. DIMORPHOSTACHYS Fourn. 

Perennial grasses with simple or somewhat branched stems, flat leaf -blades and one-sided 
racemes. Spikelets borne in pairs, the one short-, the other longer-pedicelled, the former 
with the first scale turned to one side and often much longer than the corresponding scale 
in the other spikelet. Scales 4, the outer 3 membranous ; fourth scale indurated in fruit, 
with its opening turned away from the rachis, and enclosing a palet of similar texture and 
a perfect flower. Stamens 3. Styles long, distinct. Stigmas plumose. 

Spikelets 2.3-2.5 mm. long: leaf-blades usually short, with naked margins. 1. B. Drummondii. 

Spikelets 2.&-3 mm. long : leaf-blades with ciliate margins, 2. D. dliijera. 

1. Dimorphostachys Drunundndii Fourn. Stems tufted, 3-7 dm. tall, rather slen- 
der, glabrous : leaf-sheaths glabrous excepting the ciliate margins ; blades erect, gla- 
brous, or sometimes with a few scattered hairs on the surface, generally 1.5 dm. long or 
less, occasionally longer, 1-1.5 cm. broad : racemes 2-4, 4-9 cm. long : spikelets in pairs, 
2.3-2.5 mm. long and about 1.5 mm. broad, obovate or elliptic ; scales 4 (rarely 3), the 
first and second scales rather strongly pubescent, the first scale very small, nerveless, the 
second and third scales 5-nerved, the latter glabrous. [Pospa/wm Drummondii {Fonm,) 
Vasey . ] 

In low grounds, Texas and Mexico. Summer and fall. 

2. Dimorphostachys cUlifera Nash, Stems tufted, glabrous, or sometimes papillose- 
hirsute toward the base, 7-11 dm. tall : leaf-sheaths ciliate, otherwise glabrous, or the 
lower ones papillose-hirsute ; blades erect or nearly so, the larger ones 2-3 dm. long and 
1-1.5 cm. Avide, ciliate on the margins, sparingly pubescent on the surface with scattered 
hairs : racemes 2 or 3, finally spreading, 7-9 cm. long : spikelets crowded in pairs, 2.8-3 
mm. long and about 1.8 mm. broad ; scales 4, the glabrous first scale very small or occa- 
sionally i as long as the spikelet and acuminate, nerveless, or in the latter case 1-nerved, 
the second and third scales 5-nerved, the former glabrous, the latter sparingly pubescent 
with short appressed hairs. 

In moist soil, southern peninsular Florida. Fall. 

22. ANASTROPHUS Schlecht. 

Perennial grasses, with compressed stems and sheaths, the stems creeping at the base, 
the inflorescence consisting of 2-several (rarely 1) unilateral more or less spreading spikes. 
Spikelets articulated below the empty scales, 1 -flowered, singly and alternately disposed in 
2 rows on one side of a narrow rachis, appressed, narrow, sessile, acute or acuminate. 
Scales 3, the 2 outer empty, membranous, the third one firmer, glabrous and shining, at 
length indurated, with its back turned away from the rachis, enfolding a shorter palet of 
similar texture and a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. 

Spikelets 4-6 mm. long. 1. A. paspalmdes. 

Spikelets 2-2.5 mm. long : 

Ovate : lower leaf-blades 8-12 mm. wide. 2. A, platycaulis. 

Elliptic : lowei^ leaf-blades rarely exceeding 6 mm, in width. 3. A, compressus. 

1. Anastrophus paspaloides (Michx.) Nash. Perennial, with creeping stolons. 
Stems flattened, 2-8 dm. tall : leaf-sheaths compressed and, like the blades, pubescent or 



POACEAE 



79 



glabrous ; blades commonly 2 dm. long or less, 5-12 mm. wide : spikes 4-13 cm. long, 
usually a pair at the summit of the stem, sometimes with an additional one a short distance 
below : spikelets 4-6 mm. long. [Paspalmn furcatitm Fluegge.] 

In dry sandy soil, Virginia to Florida, Arkansas and Texas. Spring to fall. 

2. Anastrophus platycaulis (Poir. ) Nash. Stolons stout and creeping. Stems 
flattened, 2-4 dm. tall : leaves glabrous or pubescent ; sheaths compressed ; blades 1.5 dm. 
long or less^ 8-12 mm. wide: spikes a pair, or sometimes with an additional one below : 
spikelets about 2,25 mm, long, ovate, very acute, pubescent. 

In dry sandy soil, Florida. Summer and fall. 

3. Anastrophus compr6ssu3 (Sw. ) Schlecht, Stolons numerous and creeping. 
Stems 3-8 dm. tall, slender, flattened : leaves glabrous ; sheaths compressed ; blades some- 
times 3 dm. long, usvially shorter, 4-8 mm. wide : spikes in paii-s, or with an additional 
third one below, slender, 4-10 cm. long : spikelets about 2 mm. long, elliptic, pubescent. 

In dry sandy soil, Virginia to Florida and Texas. Also in tropical America. Summer and fall. 

23. ANTHAENANTIA Beauv. 

Erect perennial grasses, with numerous spikelets arranged in a narrow or contracted 
panicle, Spikelets 1-2-flowered, ovate, sometimes shortly acuminate. Scales 3, the 2 
outer equal, or nearly so, membranous, densely silky-pilose externally, empty, or the 
second one enclosing a palet and sometimes also a staminate flower, the third scale equal- 
ling or a little shorter than the second, membranous, finally somewhat rigid or slightly in- 
durated, enclosing a shorter palet and a perfect flower. Stamens 3. Styles distinct. Stig- 
mas penicillate-plumose. 

Leaf-blades linear, the lower ones 3-4 mm. wide : plant often purple or purplish. *1. A. rvfa. 

Leaf-blades narrowed toward the summit, the lower ones 5-10 mm. wide : plant green. 2. A. viUosa. 

1. Anthaenantia rufa (Ell.) Schult. Smooth and glabrous, often purple. Stems 
4-10 dm. tall, from a running rootstock : leaf-^heaths shorter than the internodes ; blades 
erect, linear, obtuse, 2-5 mm, wide, those at the base and on the innovations 2-4 dm, long, 
those on the stem 2 dm, long or less : panicle contracted, 8-20 cm, long, 1-2 cm. broad : 
spikelets numerous, 3.5-4 mm. long, the first and second scales about equal in length, 
5-nerved, the hairs about 1 mm. long, the second enclosing a palet and often also a stami- 
nate flower, the third scale as long as or a little shorter than the others. 

In moist pine lands, South Carolina to'Florida. Fall.— A form, A. rufa scdbra Nash, differing from 
the above in having the sheaths and blades scabrous, occurs in similar situations in South Carolina, 
but mainly from Alabama to Louisiana. Fall. 

2. Anthaenantia vUlosa (Michx. ) Beauv. Smooth and glabrous, green. Stems 
5-15 dm. tall, from a running rootstock : leaf-sheaths shorter than the internodes ; blades 
erect, narrowed toward the apex, acute or somewhat obtuse, 3 dm. long or less, 1 cm. wide 
or less : panicle contracted, 8-20 cm. long, 1-2 cm. broad : spikelets 3-4 mm. long, the 
2 outer scales 5-nerv'ed, the hairs about 0.6 mm. long, the first scale equalling or a little 
shorter than the second which encloses a palet and sometimes also a staminate flower, the 
third scale aboiit equalling the second. 

In dry pine lands, South Carolina to Florida and Texas. Summer and fall. 

24. AMPHICARPON Raf. 

Tufted grasses, with flat leaf-blades and 1-flowered spikelets of two kinds ; one borne 
in terminal panicles, articulated below the empty scales and readily deciduous, lanceolate, 
not ripening fruit ; the other solitary, larger, becoming ovoid and turgid, terminating 
subterranean stems, and maturing fruit. Scales 3, the third subtending a palet and perfect 
flower ; the scales of the aerial spikelets green, membranous ; those of the subterranean 
spikelets much firmer in texture, white or yellowish, becoming indurated and enclosing 
the grain. Stamens 3. Styles distinct. Stigmas penicillate-plumose- 

Stems not from rootstocks : leaf-blades papillc^e-hispid. 1. A. AmpMcarpon. 

Stems from long running rootstocks : leaf-blades glabrous. 2. A. Floridanum. 

1- Amphicarpon AmphicArpon (Pursh) Nash. Stems tufted, the aerial 3-8 dm. 
tall, naked above and bearing a terminal contracted panicle 3-20 cm. long, the spikelets 
numerous, elliptic, 4-5 mm. long; subterranean stems slender, 1.5-10 cni. long, bracted at 
the base, with a single terminal spikelet : leaf -sheaths and blades papillose-his[)id with 
spreading hairs, the latter erect, 15 cm. long or less, 1.5 cm. wide or less, lanceolate. [A. 
Purshii Kunth.] 

In sandy soil, Xew Jersey to Georgia (according to Chapman). Fall. 



80 



POACEAE 



1. E. longifolia. 



2, Amphicarpon Floridinum Chapm. Stems tufted, from a long stout rootstock, 
the aerial 3-8 dm. tall, naked above and bearing a terminal contracted panicle 3-23 cm* 
long, the lanceolate spikelets numerous, 6-7 ram. long ; subterranean stems 3-15 cm. long, 
scalj at the base, with a single terminal spikelet : leaf-sheaths papillose-hispid at the 
summit and along the margins, or sometimes the loAver ones all over ; blades erect or as- 
cending, glabrous on both surfaces, or sparingly pubescent above, 2 dm. long or less, 1 
cm. wide or less, lanceolate. 

In dry sandy soil, Florida. Summer and fall. 

25. ERIOCHLOA H.B.K. 

Perennial grasses, with flat leaf-blades and an inflorescence composed of spike-like one- 
sided racemes which are racemosely arranged. Spikelets with an annular callus at the 
base, articulated below the callus, 1-flowered, imbricated, arranged in 2 rows on a flat 
rachis, acute or acuminate. Scales 3, the two outer membranous, empty, acute or 
acuminate/ the third scale glabrous and shining, shorter, at length indurated, awn-pointed 
or short -awned at the apex, enclosing a palet of similar texture and a perfect flower. Sta- 
mens 3. Styles distinct. Stigmas plumose. 

Flowering scale % as long as the spikelet or more, the awn a mere point or apiculation. 
Hairs at the apex of the pedicels none, or few and short. 

Rachis of the inflorescence and racemes puberulent or with a few scattered 

long hairs. 
Rachis of the inflorescence and racemes densely pilose with long hairs. 2. E. mollis. 

Hairs at the apex of the i>edicels many, more than ^ as long as the spikelet. 3. E. sericea. 

Flowering scale usually about % as long as the spikelet, the awn %-}4 as long as 

the scale. * 4. E. punctata, 

1. Eriochloa longifolia Vasey. Stems tufted, 4-8 dm. tall : leaf-sheaths glabrous ; 
blades erect or ascending, 4 dm. long or less, 2-4 mm. wide, smooth : inflorescence 6-20 
cm. long, its axis puberulent or with a few scattered long hairs : racemes erect, 2-4 cm. 
long, puberulent : spikelets 8-16, ovate-lanceolate, about 5 mm. long, on puberulent 
pedicels, the 2 outer scales appressed-pubescent with long hairs, 5-nerved, acute or obtuse ; 
third scale about 3.5 mm. long, coarsely transverse-rugose, about f as long as the spikelet, 
apiculate, or with a short awn less than 1 mm. long. 

In sandy soil, southern peninsular Florida. Spring. 

2. Eriochloa mollis (Michx. ) Kunth. Stems single, 7-15 dm. tall, densely and 
softly pubescent at and near the nodes : leaf -sheaths glabrous or softly pubescent with short 
avscending hairs ; blades 1-4.5 dm, long, 4-15 mm. wide, smooth and glabrous : inflores- 
cence 1.5-4 dm. long, its axis densely pilose with somewhat ascending hairs : racemes erect 
or nearly so, 8-20, 3-15 cm. long, the rachis densely pilose with somewhat ascending hairs : 
spikelets 12-40, 5-5.5 mm. long, ovate, acute, on pilose pedicels, the 2 outer scales appressed- 
pubescent with long hairs, 5-nerved, acute ; third scale about 3.5 mm. long, rather finely 
transverse-rugose, apiculate, or with a very short awn. [^Panicum molle Michx.] 

In low pine lands, South Carolina to Florida. Summer. 

i 

3. Eriochloa serfcea Munro. Stems tufted, 4-10 dm. tall, softly pubescent at and 
near the nodes : leaf -sheaths usually softly pubescent ; blades glabrous or pubescent, 4 mm. 
broad or less, those on the innovations 1-3 dm, long, those on the stem 3-20 cm. long : 
inflorescence 1-2 dm. long, its axis pubescent with short ascending hairs ; racemes ap- 
pressed, 5-9, 1-4 cm. long, the rachis pubescent with short ascending hairs : spikelets 
10-24, 4.5-5.5 mm. long, ovate, acutish, on pedicels which are densely hispid at the apex 
with hairs more than J as long as the spikelet, the 2 outer scales pubescent with rather long 
hairs, acute or obtuse ; third scale 3-3.5 mm. long, transversely rugose, apiculate. 

In dry soil, Texas and the Indian Territory to New Mexico. Summer, 

4. Eriochloa pxmctata (L.) Hamilt, , Stems tufted, 2-8 dm. tall, finally much 
branched, the nodes puberulent : leaf-sheaths and blades glabrous or pubescent, the latter 
2-30 cm. long, 3-10 mm. wide : inflorescence 6-20 cm. long, its axis pubescent with 



short ascending or nearly appressed hairs : racemes erect or nearly so, 4-20, 1.5-4 cm 
long, the rachis with short ascending haii-s : spikelets 10-30, 4.5-5.5 mm. long, lanceolate, 
acuminate, on appreased-pubescent pedicels, the 2 outer scales appressed-pubescent with 
long hairs, acuminate ; third scale transversely rugose, from i-| as long as the spikelet, 
about 2.5 mm. long, exclusive of the hispid awn which is J as long as the scale or more. 

On plains or prairies, Kansas to Texas. Summer and fall. Everlasting Grass. 

26. BRACHIARIA Ledeb. 

Grasses with flat leaves and the spikelets borne in 2 rows in one-sided spikes. Spikelets 
of 4 scales, the outer 3 membranous, the fourth scale chartaceous, indurated in frviit, trans- 

i 



rOACEAE 



81 



versely rugose, and enclosing a similar palet and a perfect flower, its opening turned toward 
the rachis. Stamens 3. Styles distinct. Stigmas plumose. 

1. Brachiaiia platyphylla (Monro) Xash. Stems at first erect, finally prostrate and 

rootine: at tlie lower nodes. 4-6 dm. lone* : leaf-sheaths nnhpsr^pnt. poTrimnnlv n^rar^iir^r^^ntT • 



:es 2-5, rather distant, 3-6 
about 4 mm. lone*. 



woods, Louisiana and Texas. Summer and fall. 



3. S. leucocomum. 



4. S. gracilUnium, 

5. S, Bakeri, 



27. SYNTHERISMA Walt. 

Annual grasses, with flat leaf-blades and an inflorescence composed of spike-like racemes 
Avhich are disposed in whorls, or scattered and approximate, at the summit of the stems. 
Spikelets narrow, acute, in 2's or 3's on one side of the flat and winged or triangular rachis, 
one of the spikelets generally longer pedicelled than the rest. Scales 3 or 4, the 3 outer 
membranous, the first small or wanting, tlie fourth scale chartaceous, glabrous and shining, 
at length indurated, enclosing a palet of similar texture and a perfect flower. Stamens 3. 
Styles distinct. Stigmas plumose. [Digitaria Scop., not Heist] Crab Grass. 

Rachis of the racemes with the angles naked, not winged : first scale wanting or 
sometimes present as an inconspicuous rudiment. 
Second and third scales pubescent with appressed glandular tipped hairs : stems 
simple or sparingly branched at the base ; nodes 5 or fewer. 
Racemes usually short, 2-10 cm. long : spikelets less than 2 mm. long. 1. S, filifomie. 

Racemes usually exceeding 10 cm. in length, rarely shorter: spikelets 2.25 
mm. long or more. 
Pubescence on the sheaths spreading: racemes commonly more than 5. 2. S, villosum. 
Pubescence on the sheaths appressed or nearly so : racemes commonly 
less than 4. 

Second and third scales glabrous. 

Hairs on the sheaths appressed or nearly so : nodes 5 or fewer. 

Second scale J^ as long as the spikelet or less, rounded or truncate at the 

apex. 
Second scale more than y^ as long as the spikelet, sparingly pilose at the 
acute apex. 
Hairs on the sheaths widely spreading: nodes numerous. 6. S. Simpsonu. 

Rachis of the racemes with the lateral angles broadly winged, thus making it 
appear flat : first scale usually present, or generally wanting in nos. 7 and 8. 
Pedicels terete or sometimes obscurely angled, sparingly if at all hispidulous. 
Sheaths and leaf-blades strongly papillose-hirsute: rachis of the racemes 

0.8 mm. wide or less ; second scale K as long as the spikelets or less. 7. S, aerotinum. 

Sheaths and leaf-blades glabrous : rachis of the racemes 1 mm. wide or 

more ; second scale nearly as long as the spikelet. 8. S. humifusum. 

Pedicels sharply 3-angled, the angles strongly hispidulous. 

Sheaths strongly papillose- hirsute : racemes commonly more than 3. 

Racemes very slender, the rachis usually less than 0.5 mm. wide : spike- 
lets 1/5 as wide as long, acuminate: fourth scale greenish when ma- 
ture. 
Racemes stouter, the rachis usually exceeding 0.7 mm. wide : spikelets 3^ 
as wide as long or more, acute : fourth scale yellowish white when 

mature. 
Spikelets usually less than 3 mm. long, the second scale J^ as long as 
the spikelet or less, the third scale with the first and second nerves 
on each side hispid above the middle. 10. S, sanguinale, 

Spikelets commonly more than 3 mm. long, the second scale more 
than K as long as the gpikelet, the third scale with the nerves 
smootn. 11- S. flmbriatum. 

Sheaths glabrous or nearly so : spikelets about 4 mm. long : racemes 2. 12. S. barbatum. 

1. Syntherisma filifdrme (L. ) Nash. Stems 1.5-7 dm. tall : leaf-sheaths papillose-hir- 
sute, or the uppermost one glahrous ; blades 3-20 cm. long, 1-4 mm. wide, erect, usoally 
glabrous below, papillose-hirsute above toward the base : axis of tlie inflorescence 1-3 cm. 
long: racemes 2-5, 2-10 cm. long, erect or ascending, alternate: spikelets about 1.8 mm. 
long, 0.75 mm. wide, elliptic, acute, in pairs; first scale wanting, the second and third 
scales appressed-pubescent with long glandular-tipped hairs, the former 3-nerved and about 
I as long as the 7-nerved third scale, the fourth scale slightly exceeding the third, deep 
chestnut brown when mature, striate. [Panicum filiforme L.] 

In dry sandy soil, Massachusetts to Michigan, North Carolina and the Indian Territory. Summer. 

2. Syntherisma villosum Walt. Stems densely tufted, 6-14 dm. tall: lower leaf- 
sheaths papillose-hirsute, the uppermost one sometimes glabrous ; blades 7-25 cm. long, 
3-6 mm. wide, erect or nearly so, smooth beneath, rough above, the lower surface more or 
less papillose-hirsute, the upper leaves glabrous : axis of the inflorescence 3-9 cm. long ; 
racemes 2-8, usually more than 5, generally 12-15 cm. long, erect or ascending, alternate : 
spikelets 2.5 mm. long, about 0.8 mm. wide, elliptic, acute, usually in S's, the first scale 
wantuig, the second and third scales appressed-pubescent with long ghindular-tipped hairs, 

6 



9. S. setosvm. 



82 



POACEAE 



the second scale 3-nervecl, a little shorter than the 7-nerved third, the fourth scale slightly 
exceeding the third, deep chestnut hrown when mature, striate, apiculate. 

In sand}' soil, Illinois to the Indian Territory, Georgia and Texas. Summer. 

3. Syntherisma leucocomum Xash. Stems 1 m. tall or less : leaf-sheaths coarsely 
striate, the lower one densely hirsute with nearly appressed hairs ; blades erect, often invo- 
lute when dry, smooth beneath, rough above, those on the stem 1.5-2.5 dm. long, those 
on the innovations 1-4 dm. long : axis of the inflorescence 4-6 cm. long ; racemes 2-4, 
2-2.5 dm. long, erect or nearly so, alternate : spikelets 2.25-2.5 mm. long, 0.8 mm. wide, 
elliptic, acute, usually in 3's; first scale wanting, the second and third scales appressed- 
pubescent with very long glandular-tipped haii-s, the second scale about as long as the 
fourtli, 3-nerved, the third scale a little longer than the fourth, .7-nerved, the fourth scale 
trown at maturity, striate, apiculate. 

In high pine lands, Florida, Summer. 

4. Syntherisma gracillimum (Scribn.) Nash. Stems tufted, 6-8 dm. tall, the inno- 
vations mostly about 2 as long : lower leaf-sheaths somewhat hii^ute with ascending-ap.- 
pressed hairs ; blades 2 mm. wide or less, smooth beneath, rough above, those on the inno- 
vations 3-4 dm. long ; axis of the inflorescence 3-C cm. long ; racemes 2, or rarely 3, about 
3 dm. long, erect : spikelets slightly exceeding 2 mm. long, about 0.8 mm. broad, elliptic, 
acute, usually in 3's, irregularly scattered ; scales glabrous, the first wanting, the second 
3-nerved, usually about } as long as the spikelet, the third scale 5-nerved, slightly shorter 
than the spikelet, the fourth scale deep seal brown when mature, conspicuously striate, ob- 
tusely angled on the back, apiculate. 

In high pine lands, Florida. Summer. 

5. Syntherisma Bkkeri Nash. Stems tufted, 1 m. tall or less : lower leaf-sheaths 
densely hirsute with ascending hairs ; blades 2 mm. wide or less, involute when dry, 
smooth, densely pubescent above at the base, those on the innovations 2-4 dm. long, those 
on the stem 1-2.6 dm. long: axis of the inflorescence 4-7 cm. long; racemes usually 3, 
14-22 cm. long, densely long-pilose at the base : spikelets about 2.25 mm. long, 0.8 mm. 
-wide, elliptic, usually in 3's ; scales glabrous, excepting the sparsely pilose apex of the 
second, the fii'st one wanting, the second about | as long as the spikelet, acute or acutish, 
3-nerved, the third a little shorter than the fourth which is deep chestnut brown when ma- 
lure, elliptic, obtusely apiculate and rather faintly striate. 

In dry sandy soil, Florida. S'mmer. 

6. Syntherisma Slmpsonii ( Vasey) Nash. Stems 8-12 dm. long, finally branched, 
prostrate at the base and rooting at the lower nodes : leaf-sheaths copiously papillose-hir- 
sute with spreading hairs ; blades 7-30 cm, long, 5 mm. wide or less, papillose-hirsute on 
both surfaces : axis of the inflorescence 4-6 cm. long ; racemes 6-8, 10-13 cm. long, erect 
or ascending, usually scattered : spikelets a little exceeding 3 mm. long, aboilt 1 mm. 
wade, elliptic-lanceolate, acute, in pairs ; scales glabrous, the first one usually wanting, 
the second and third about equal in length, the former 5-, the latter 7-nerved, the fourth 
a little shorter than the third, elliptic, acute, yellowish white, finely striate. 

In moist saline soil, Florida. Summer. 

7. Syntherisma serdtinum Walt, Stems 2-5 dm. long, finallv branched, prostrate 
at the base and rooting at the lower nodes ; leaf-sheaths, especially the lower ones, papil- 
lose-hii^ute with spreading hairs ; blades 1,5-10 cm. long, 3-10 mm. wide, ascending, pu- 
bescent on both surfaces : axis of the panicle 1-2 cm. long ; racemes 2-6, 2,5-10 cm. long, 
ascending, usually alternate : spikelets about 1.5 mm. long, about 0.6 mm. wide, elliptic, 
acute, usually in pairs ; first scale wanting, the second and third appressed-pubescent with 
long hairs, the second one about ^ as long as the spikelet, 3-nerved, the fourth a little 
longer than the third, white, ovate-lanceolate, acute. [^Panicum serotinum Trin.] 

In low open grounds, Delaware to Florida and Mississippi. Summer. 

8. Syntherisma hiimifusum (Pers. ) Rydb. Stems 2-5 dm. long, finally branched, 
prostrate and forming large mats: leaf -sheaths glabrous; blades 1,5-15 cm. long, 2.5-6 
mm. wide, erect or nearly so, smooth and glabrous on both surfaces : axis of the inflores- 
cence 1-3 cm. long ; racemes 2-5, 2-8 cm. long, finallv widely spreading, alternate : spike- 
lets slightly exceeding 2 mm. long, about 1 mm. wiae, elliptic, acutish, usually in pairs ; 
first scale usually wanting, the second and third appressed-pubescent, the 3-nerved second 
about equalling the 7-nerved third, the fourth one a little longer than the third, deep 
chestnut brown w^hen mature, striate, acute. [^Panmtm glabrum Gaud.] 

In waste places and fields, Ontario to Kansas, Florida and Louisiana.— A form, S. humifitsum Mis- 
mssippiense f Gattinger) Nash, differs from the above in ha\*ing usually longer racemes and the first scale 
of the spikelet generally present. Cedar barrens, Nashville, Tenn. Summer. 

9. Syntherisma aetosum ( Desv. ) Nash. Stems tufted, 4-10 dm. tall, finally branched, 
decumbent at the base and rooting at the lower nodes: leaf-sheaths, excepting the upper- 



POACEAE 



83 



most one, densely papillose-liirsiite with spreading liairs ; blades 2-12 cm. long, 2-7 mm. 
wide, papillose-hirsute on both surfaces : axis of the inflorescence 4 cm. long or less ; 
racemes 4-13, 4-13 cm. long, finally "widely spi'eading, usually in a whorl at the base and 
the remainder alternate or approximately in pairs: spikelets about 2.5 mm. long, about 
0.5 mm. wide, lanceolate, acuminate, in pairs, occasionally with a delicate basal bristle ; 
first scale minute, glabrous, the second and third scales appressed-pubescent, tlie second 
3-nerved, about J as long as the spikelet, the third 7-nerved, noticeably longer than tlie 
fourth one which is slightly less than 2 mm, long, elliptic, greenish when jnature. 

In dry sandy soil, Florida. Also in the West Indies and South America. Summer. 

10. Syntherisma sanguiD^le (L. ) Dulac. Stems 1 m. long or less, finally branched, 

E rostrate at the base and rooting at the lower nodes : lower leaf-sheaths densely papillose- 
irsute ; blades 4-20 cm. long, 4-10 mm. wide, more or less papillose-hirsute on both sur- 
faces : axis of the inflorescence 1 cm. long or less ; racemes 3-10, 5-18 cm. long, usually 
erect or ascending, commonly digitate; spikelets 2.5-3 mn). long, about 0.8 mm. wide, 
elliptic-lanceolate, acute, in pairs ; first scale small, glabrous, the second and third appressed- 
pubescent, the second about ^ as long as the spikelet, ovate-lanceolate, 3-nerved, the third 
about as long as the flowering one, 7-nerved, the first and second nerves on each side hispid 
above the middle, fourth scale yellowish white when mature, acutely apiculate, elliptic- 
lanceolate. \_Panicum sanguinale L.] 

In cultivated places, nearly throughout North America. Introduced. Spring to fall. 

11. Syntherisma fiinbri^tum (Link) Nash. Stems 8 dm. long or less, finally 
branched, prostrate at the base and rooting at the lower nodes : lower leaf sheatl\s densely 
papillose-hirsute with spreading hairs; blades 2-8 cm. long, 5-10 mm. wide, erector 
ascending, both surfaces glabrous or more or less pubescent : axis of the inflorescence 2 cm. 
or less long ; racemes 2-9, 2-12 cm. long, erect or ascending, alternate, in pairs or whorls : 
spikelets 3-3.5 mm, long, about 0.8 mm. wide, lanceolate, very acute, in pairs ; fii'st scale 
small, glabrous, the second and third appressed-pubescent with long hairs, the second one 
4 to ^ as long as the spikelet, lanceolate-cuneate, 3-nerved, the third slightly exceeding the 
flowering scale, 7-nerved, the pubescence usually becoming widely spreading, the fourth 
one lanceolate, very acute, yellowish white at maturity. 

• In dry sandy soil, District of Columbia to Florida and Texas. Introduced. Summer. 

12. Syntherisma barbktum (Willd. ) Nash. Stems 5 dm. long or less, branching, 
often rooting at the low^er nodes : leaf -sheaths glabrous ; blades lanceolate, 3 cm. long or 
less, 3-5 mm. wide, glabrous on both surfaces, sparsely ciliate at the base : racemes in 
pairs, 4-6 cm. long, erect or ascending: spikelets 3.5—4 mm. long, slightly exceeding 1 
mm. wide, lanceolate, acute, in pairs; first scale small, glabrous, the second and third 
appressed-pubescent with very long hairs, the second one about f as long as the spikelet, 
lanceolate-cuneate, 3-nerved, the third 7-nerved and in the long-pedicelled spikelet the 
pubescence of two kinds ; fourth scale yellowish white at maturity, elliptic-lanceolate, 
acuminate. 

In sandy soil, Mississippi. Introduced. Summer, 

28. TRICHACHNE Nees. 

4 

Perennial grasses, with flat leaf-blades, usually tufted stems and narrow or contracted 
panicles, usually densely hairy, Spikelets numerous, articulated below the empty scales, 
1-flowered, lanceolate, 'acute or acuminate. Scales 4, the outer 3 membranous, empty, the 
second and usually also the much shorter first densely silky-pilose or long-ciliate on the 
margins, often acuminate, and sometimes with a short bristle at the apex, the fourth scale 
shorter, chartaeeous, glabrous and shining, finally indurated, enclosing a shorter palet of 
similar texture and a perfect flower. Stamens 3. Styles distinct. Stigmas j)lumose. 

Panicle tawny white : spikelets 4-5 mm. long, lanceolate. 1. T, inaulave. 

Panicle silvery white : spikelets about 3 mm. long, ovate-lanceolate. 2. T. saccharatum, 

1- Trichachne instU^re (L. ) Nash. . Stems 1-1.5 dm. tall, stout, finally more or less 
branched : leaf-sheaths usually glabrous, or sometimes papillose-hirsute ; blades ascending, 
sometimes drooping, 1-3 dm. long, generally 5-20 mm. wide : panicle tawny white, usualFv 
2-3 dm. long, 1-2 cm. wide : spikelets 4-5 mm. long, long-acuminate, the hairs less copious 
than in the following species. IPanicum leucophaeum II.B.K.] 

In cultivated ground, on banks, and in coral soil, Florida and southern Texas. Also in tropical 
countries. Spring to fall. 

2. Trichachne sacchar^tum (Buckl.) Nash. Stems 4-8 dm. tall, finally somewhat 
branched: leaf-sheaths glabrous, or sometimes papillose-hirsute ; blades erect or ascending, 
generally iess than 1.5 dm. long and usually less than 5 mm. wide : panicles silvery white, 



84 



POACEA E 



1. E. colona. 

f 

2. E. Crus-gallL 



1-2 dm, long, usuallv 1.5 cm. Avide or less: spikelets ovate-lanceolate, acute, 3-3.5 mm. 
long, the silvery Avliite hairs very long and copious, extending much beyond the apex of 
the spikelet. 

On dry hillsides, Texas to Colorado. Also in Mexico. Summer. 

29. ECHINOCHLOA Beauv. 

Often tall grasses, with flat leaf-blades, the inflorescence composed of several to many 
unilateral more or less spreading spike-like racemes. Spikelets 1-2-flowered, lanceolate to 
ovate or orbicular-ovate, crowded in small clusters or racemes in 2 rows on one side of the 
flat rachis. Scales 4, the 3 outer membranous, spiny-hirsute or hispid externally, the first 
much shorter than the spikelet, often awn-pointed, the second and third awn-pointed or 
awned (rarely awnless), the latter bearing the longer awn and rarely enclosing a palet and 
sometimes also a staminate flower ; fourth scale chartaceous, glabrous and shining, at length 
indurated, acute or acuminate, enclosing a shorter palet of similar texture and a perfect 
flower. Stamens 3. Styles distinct. Stigmas plumose. 

Leaf-sheaths glabrous. 

Awn of the third scale not exceeding 4 times the length of the spikelet, some- 
times very short or almost wanting. 
Spikelets 2.5-3 mm. long : lower racemes rarely exceeding the rachls-inter- 

nodes. 
Spikelets 4 mm. long ; the lower racemes much exceeding the rachis-inter- 
nodes. 
Awn of the third scale 8-15 times the length of the spikelet, 3. E. longearisfata. 

Leaf-sheaths, at least the lower ones, densely papillose-hispid. 4. E. Walteri, 

1. Echinochloa colona (L. ) Link. Stems tufted, 1-8 dm. tall, often decumbent 
and rooting at the lower nodes : leaf-sheaths glabrous, compressed ; blades flat, 2-17 cm. 
long, 2-8 mm. w^ide : inflorescence composed of 3-18 one-sided more or less spreading ra- 
cemes, 6-30 mm. long : spikelets single, in pairs, or in 3's in 2 rows, obovate, pointed, his- 
pid on the nerves, 2.5-3 mm. in length, the fourth scale cuspidate. \_Panicum colonum L.] 

In fields and along roadsides, Virginia to Florida, Texas and Mexico. Common in all tropical 
countries. Spring to fall. Jungle Rice. 

2. Echinochloa Crus-galli ( L, ) Beauv. Stems 6-12 dm. tall : leaf-sheaths glabrous ; 

blades 1.5-6 dm. long, 6-25 mm. wade, glabrous, smooth or rough : panicle of 5-15 erect 

or ascending branches, or the lower ones spreading or reflexed and sometimes 6-8 cm. long : 

spikelets ovate, densely crowded in 2-4 rows on one side of the rachis, about 4 mm. long, 

exclusive of the awn, hispidulous, hispid on the nerves, the second and third scales more 

or less awned, the fourth abruptly pointed. [Panicum Orus-galli L.] 

In cultivated and waste places throughout North America, excepting the extreme north, and 
widely distributed as a Aveed in all cultivated areas. Introduced from Europe. Summer and fall. 
Barnyard Grass. 

3. Echinochloa longearistkta Nash. Stems 1-2 m. tall, stout : leaf-sheaths gla- 
brous ; blades flat, rough on the upper surface, smooth beneath, 6-12 dm. long, 2-4 cm. 
wide or more : panicle 4-6 dm. long, its branches ascending : spikelets ovate, 3.5-4 mm. 
long, acuminate, hispidulous, the nerves strongly hispid, the awn of the third scale usually 
8-15 times as long as the spikelet. 

In wet ground, South Carolina to Louisiana. Summer. 

4. Echinochloa "Wdlterl (Pursh) Nash. Stems 9-18 dm. tall, stout : leaf -sheaths, at 
lea^t the lower ones, papillose-hispid ; blades 3 dm. long or more, 1-2.5 cm. wide, very 
rough above : panicle of 10-40 ascending or spreading branches : spikelets ovate-lanceolate, 
densely crowded in 2-4 rows on one side of the rachis, 3-4 mm. long, exclusive of the awns, 
hispidulous, hispid on the nerves, the second and third scales very long-awned, the fourth 
scale ovate-lanceolate, acuminate. 

In marshes and ditches, usually near salt-water, New York to Florida. Summer and fall. 

30. OPLISMENIIS Beauv. 

Perennial grasses, often decumbent and branched at the base, with broad flat leaf- 
blades and inflorescence composed of spikes, bearing on the lower side scattered clusters of 
a few spikelets. Spikelets 1-flowered. Scales 4, the 3 outer membranous, the first and 
second empty, awned, the first equalling or somewhat shorter than the spikelet, the third 
scale usually awned, empty, or enclosing a small palet, the fourth one shorter than the 
others, obtuse, awnless, chartaceous, finally indurate, enclosing a shorter palet of similar 
texture and a perfect flower. Stamens 3. Styles distinct to the base. Stigmas plumose. 

Oplismenus setirius (Lam.) R. & S. Stems prostrate, rooting at the nodes: leaf- 
blades ovate to ovate-lanceolate, acuminate, 1.5-6 cm. long: panicle 2-8 cm. long, its short 



'I 

1 



POACEAE 



85 



Tjranches erect to spreading : spikelets, exclusive of the awns, 2.5-3 mm. long, the longer 



awns 6-8 mm. long. 



In low woods and swamps, Georgia to Texas. Also in tropical America. Summer and fall. 



I. PASrALOIDEA. 



II. VERRUCOSA. 



III. CAPILLARIA. 



IV. IIALOnilLA. 

V. VIRGATA. 
VI. MAXIMA. 
VII. AGROSTOIDEA. 



31. PANICUM L. 

Annual or perennial grasses, varying much in habit, with elongated or flat and broad 
leaf-blades, and the spikelets in open or contracted panicles. Spikelets 1-2-flowered, lance- 
olate, oblong, ovate to obovate or globose, obtuse to acute or acuminate. Scales 4, the 
3 outer membranous, the first and second empty, the first usually much shorter than the 
spikelet, sometimes minute, the third one empty or enclosing a shorter hyaline palet and 
often also a staminate flower ; fourth scale shorter and usually more obtuse than the others, 
chartaceous, glabrous and shining, at length indurated, enclosing a palet of similar texture 
and a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. 

Herbs, varying in habit. 

Spikelets disposed singly or in pairs in one-sided racemes, the pedicels short. 
Spikelets arranged in panicles but not disposed in one-sided racemes, the 
pedicels short or long. 
Basal leaf-blades long and narrow, similar to those of the stem : no rosu- 
late tufts of leaves in the fall : spikelets lanceolate to ovate, usually 
the former, acute to acuminate, rarely obtuse. 
Spikelets manifestly tuberculate. 
Spikelets not tuberculate. 

Basal leaf-sheaths round or but little flattened, not keeled.' 
Fourth scale smooth. 

Annuals or perennials, if the latter no rootstocks or stolons. 
Perennial by long rootstocks or stolons. 

Rootstocks and stolons naked or with a few large scales : 

sandbinders. 
Rootstocks, at least when young, and stolons covered with 

numerous small broad acute scales. 
Fourth scale transversely rugose. 
Basal leaf-sheaths much compressed, broad, keeled, often equitant. 
Basal leaf-blades commonly unlike those of the stem, ovate to ovate- 
lanceolate : perennial by rosulate tufts which form in the fall at the 
base of the stems : spikelets elliptic to spherical, usually obtuse, some- 
times acute, never acuminate. VIII. DICHOTOMA. 
Much branched shrubs, with broad leaf-blades: spikelets large and turgid, the 

outer scales woolly-tipped. IX. LATIFOLIA. 

I. PASPALOIDEA. 
Fourth scale of the spikelet smooth. 

Spikelets not ciliate with long hairs, the first scale 3^ as long as the spike- 
let or less, excepting in no. 2. 
Terrestrial grasses. 

Stems prostrate : leaf-blades short, ovate-lanceolate, spreading. 
Stems erect : leaf-blades long and relatively narrow. 

Spikelets obtuse, turgid, the first scale very large, rounded at the 

apex, more than % as long as the spikelet. 
Spikelets acute, the first scale small, acute at the apex, less than 
% as long as the spikelet. 
Aquatic grasses. 

Spikelets singly disposed, about 3 mm. long, the first scale rounded 

or truncate at the apex. 
Spikelets in pairs, about 2 mm. long, the first scale acute at the sum- 
mit. 
Spikelets ciliate with numerous very long hairs, the first'scale narrow and 

acuminate, nearly as long as the spikelet. 
J'ourth scale transversely rugose: usually the outer scales of some or all of 
the spikelets with anastomosing veinlets. 
Branches of the panicle terminated by a spikelet, no extension beyond 
them. 
Spikelets 2.5-3 mm. long, broadly obovoid, obtuse or acutish, anasto- 
mosing veinlets numerous and prominent. 
Spikelets 4-6 mm. long, acute or acuminate, oval, anastomosing vein- 
lets few and faint. 
Spikelets about 4 mm. long, the first scale less than >^ then* length. 
Spikelets 5-6 mm. long, the first scale more than % their length. 
Branches of the panicle extending beyond the spikelets in an awn-like pro- 
jection. 
First scale of the spikelet 1-nerved, or sometimes with a famt lateral 

nerve on each side. 
Ftet scale of the spikelet 5-nerved. 

Spikelets 2.5 mm. long : leaf-blades usually short. 
Spikelets 3.5 mm. long : leaf-blades usually elongated. 



1. P. prostratam 



2. P. obtusum, 

3, P. mnlle. 



4. P. pcuipalfndes. 

5. P. digitarioides, 

6. P. ciliaiwdmum. 



7. P. ftisrvm. 



8. P. /aaciculcUurn. 

9. P. Tezauum, 



10. P. Chapmanii, 

11. P. ramisetuvi, 

12. P. Reverchonii. 



II. v?:rrucosa. 

Spikelets about 2 mm. long, the tubercles not hair-bearing. 
Spikelets alx)ut 3 mm. long, each tubercle bearing a short stout hair 



13. P. rerrnrogum. 
11. P. brarhyanthnm 



86 



POACEAE 



III. CAPILLARIA. 
Annuals. 

Spikelets 3 mm. long or less, lanceolate or elliptic. 
Leaf-sheaths pubescent. 

Stems stout : panicle usually included at the base, its many branches 

repeatedly divided and bearing numerous spikelets. 
Stems slender: panicle exserted, its few branches but little divided 
relatively and bearing comparatively few spikelets. 
Spikelets 2 mm. long, acute. 

Spikelets lanceolate, about 0.6 mm. wide. 
Spikelets elliptic, about 0.8 mm. wide. 
Spikelets 3 mm. long, acuminate. 
Leaf-sheaths glabrous. 

First scale about M as long as the spikelet. 
First scale more than y^ as long as the spikelet. 

Spikelets ovate, the panicle branches ascending: leaf-blades 1.5 
dm. long or less. 

Spikelets lanceolate, the panicle branches very long and wide- 
spreading: leaf-blades 2.5-4 dm. long. 
Spikelets 5 mm. long, ovate. 
Perennials. 

Spikelets less than 4 mm. long. 

Pedicels usually not exceeding four times the length of the spikelets, 
often shorter than them. 
Stems densely tufted, stiff and wiry, slender. ^ 

Panicle branches appressed. 
Panicle branches at maturitv spreading. 
Stems single or not much tufted, stout, not rigid and wiry. 

Spikelets ovate, the panicle branches ascending: leaf-blades 1.5 

dm. long or less. 
Spikelets lanceolate, the panicle branches very long and widely 
spreading : leaf-blades 2.5-4 dm. Ion 
Pedicels usually many times exceeding the spilkelets. 
Spikelets 5-C mm. long, acuminate. 

IV. HALOPHILA. 

Spikelets less than 3 mm. long, obtuse or acutish. 

Panicle dense, the spikelets crowded, the first scale of the spikelet acute, 

about % as long as the spikelet. 
Panicle long and narrow, loose, the spikelets rather scattered, the first 
scale of the spikelet truncate, about 34 as long as the spikelet. 
Spikelets 5-6 mm. long, acuminate. 

V. VIRGATA. 

Stems tall, simple : panicle usually ample. 

VI. MAXIMA. 

Tall stout grasses, with large leaves and ample panicles. 



15. P. capillars 



IG. P. Philadelphicxim 

17. P. (fatfingeri. 

18. P. flexile, 

19. P. proliferum. 



23. P. ffalllL 

24. P.filipes.' 
20. P. luillaceum. 



21. P. sf modes, 

22. P. diffusum. 



23. P. IlalUL 

24. P. fllipes, 

25. P. co(/natum. 

26. P. capillanoides 



27. P, haloph llttm 

28. P. repens. 

29. P. amarum. 

30. P. virgatum. 



31. P. maximum. 



VII. AGROSTOIDEA. 

Innovations intravaginal, hence stems tufted ; spikelet not oblique to the 
pedicel, the apex straight, hence equilateral. 
Fourth scale of the spikelet sessile. 
Lignle membranous. 

Panicle ovate, its branches at maturity widely spreading. 
Panicle oblong, its branches erect. 
Ligule a ring of long hairs. 

Leaf-sheaths naked at the apex ; panicle branches rigid and spread- 
ing at maturity. 
Leaf-sheaths pubescent with long hairs at the apex on the outside : 
panicle branches long and slender, erect, fiexuous. 
Fourth scale of the spikelet Avith a distinct slender stipe. 
Innovations extravaginal, the long stolons stout and scaly : spikelet oblique 
to the pedicel, the apex decidedly curved, hence inequilateral. 



32. P. agrost&ides. 

33. P. cbndensam. 



34. P. Combsiu 

35. P, pseudanccps 

36. P. stipitahim, 

37. P. rostratum. 



VIII. DICHOTOMA. 

A. Leaf-blades on the stem long and narrow, linear, narrowed at both ends, 
very different from the early basal ones, 
a. Leaf-blades erect. 

Stems 8-14 dm. tall, stout. 

Stems less than 6 dm. tall, not stout. 

Primary leaf-blades of the stem usually less than 4 mm. wide, from 
25-50 times as long as broad. > 
Stems simple, finally with very short spikelet-bearing basal stems 
concealed in the leaves : spikelets 2 mm. long or more. 
Spikelets obtuse, the outer scales as long as or but little shorter 
than the fourth scale. 
Spikelets 2-2.5 mm. long, pubescent. 

Spikelets 3 mm. long, with a few scattered hairs near the 
base. 
Spikelets acute, glabrous, the outer scales manifestly exceeding 
the fourth scale. 
Stems filially branchini^r at the nodes, no .short basal stems : spike- 
lets 1.5 'mm. long or less. 
Primary leaf-blades of the stem exceeding 4 mm. wide, often more 
than 1 cm. in widtti, 20 times as long as broad or less. 



105. P. scahrimcidum^ 



38. P. linearifoliu/n. 

39. P. perlongitm, 

40. P. depmiperatum, 

41. P. gkihrifoUum, 



poaceap: 



87 



Stems simple, or sometimes sparingly branched at the nodes: 
plants usually bright green : hairs on the leaf-sheaths re- 
flexed. 

Hpikelets 1.7-2 mm. long : leaf-blades usually pubescent, some- 
times nearly glabrous, commonly ciliate on the margins. 

Spikelets about 2.5 mm. long : leaf-blades glabrous, excepting 
sometimes a few hairs on the margin. 

Stem? at length repeatedly dichotomous-branched, forming dense 
mats : plants grayish green : hairs on the leaf-sheaths, if any, 
ascending or appressed. 
Whole plant, excepting the spikelets, glabrous or nearly so, or 
the sheaths and blades sometimes pubescent. 
Spikelets broadly obovoid, about 2 mm. long. 
Spikelets obovoid, 2.5-3.5 mm. long. 
Whole plant, including the upper part of the stem, densely 
villous. 
b. Leaf-blades widely spreading. 
B. Leaf-blades of the main stem differing from the above, usually lanceolate 
to ovate-lanceolate, sometimes short and linear. 
Stems simple, or rarelya little branched at the lower nodes, forming 
dense tufts. 
Leaf-sheaths hirsute. 

Spikelets less than 1.5 mm. long. 
Spikelets exceeding 1.5 mm. long. 
Leaf-sheaths glabrous, excepting the ciliate margin ; blades strongly 
and beautifully ciliate on the margins, otherwise glabrous, 
Spikelets about 1.5 mm. long, glabrous. 
Spikelets 1.8-2 mm. long, pubescent. 
Stems finally branching at the upper nodes (sometimes remaining simple 
in number 89), often repeatedly branching. 
* Middle leaf-blades of the main stem less than 1.5 cm. in width, usually 
less than 1 cm. wide, the base rounded or truncate, sometimes in 
the broadest ones cordate. 
t Leaf-sheaths glabrous or puberulent, the lower ones sometimes 
with a few scattered long hairs, the margins often ciliate. 
Stem nearly naked above the base, a single leaf above the mid- 
dle of the stem. 
Stems leafy. 
Xodes barbed. 

Spikelets glabrous : 

A little less than 2 mm. long. 
About 2.5 mm. long. 
Spikelets pubescent. 
Nodes naked. 

Spikelets glabrous. 

Spikelets less than 1.5 mm. long. 

Stems densely tufted, less than 3 dm. tall, finally 
much-branched and prostrate and forming large 
mats : spikelets about 1 mm. long. 
Stems exceeding 6 dm. tall : spikelets about 1.3 mm. 
long. 
Spikelets 1.5-2 mm. long. 

Leaf-blades ciliate with long hairs, at least for the 

lower half. 
Leaf-blades not ciliate. 

Primary leaf-blades of the stem large, 9-12 cm. 

long. 
Primary leaf-blades of the stem small, rarely ex- 
ceeding 6 cm. long. 
Leaf-blades widely spreading, thin. 

Stems remaining erect, branching at the mid- 
dle, the late state assuming the form of 
a little tree. 
Stems becoming prostrate, branching their 
whole length. 
Leaf-blades erect: 

Thin : stems finally much-branched and pros- 
trate. 
Ligule membranous, 0.25 mm. long to al- 
most wanting: spikelets elliptic. 
Ligule of erect hairs about 1 mm. long: 
spikelets obovoid. 
Firm, the basal ones thick and much broader 
than the upper. 

Spikelets 2.5-3 mm. long : 

Elliptic : stems finally much-branched and prostrate. 

Broadlv obovoid : stems erect. 

Spikelets pubescent. 

g Spikelets less than 2 mm. long. 

Leaf-blades ciliate for at least % their length. 
Panicle ovoid: spikelets few, 1.75mm. long: 

blades small. 
Panicle oblong: spikelets numerous, 1.3 mm. long: 

leaf-blades large. 
Leaf-blades naked on the margins, or sometimes with 

few long hairs at the very base.- 



46. P. Icuiflorum. 
45. P. pyrifonne. 



47. 
48. 

49. 
107. 



P. neAtrantkxim, 
P. angustifoUuiiu 

P. coiisangalneum, 
P. equUaierale. 



42. 
46. 



P. fitrtgosuni, 
P. laxiforum^ 



43. 

44. 



P. polijcaulou^ 
P. ciliatiim. 



66. P. niulicaule. 



57. P. harbulatum. 

58. P. neinopanthum. 

59. P. Mattamuskeetense. 



68. P. BaldwiniL 
78. P. octonodnm. 



52, P. Xashianum. 



5^. P. Yadkinense. 



55. P. dichotomum, 
62. P. lueidiim. 



62. P. lucidam. 

63. P. curt ivagi nam, 
51. P. Roanokei\fi€, 

65. P. sphagnicoln. 
116. P, pernervosarnu 



leaf- 



52. P. Xashianum. 
91. P. erect {folinm. 



88 



POACUVE 



Spikelets less than 1 mm. long. 
Spikelets 1-2 mm. long. 

Ligule 0.5 mm. long to almost wanting. 

Blades of the primary stem-leaves, the larger 
ones, 8-15 mm. wide. 
Spikelets 1.3 mm. long: basal leaf-blades 
equalUng or larger than those on the 
stem wiiieh are usually 5-7 in number. 
Spikelets 1.5 mm. long or more ; basal leaf- 
blades smaller than those on the stem 
which usually number 4 or less. 
Upper surface of the blades very rough. 
Upi)er surface of the blades smooth : 

stems much-branched : sheaths in- 
flated. 

Blades of the primary stem-leaves, the larger 
ones, rarely exceeding 6 mm. wide : 
With a broad cartilaginous white much- 
thickened margin. 
Upper portion of the stem naked, the 2 

leaves below the middle. 
Stems leafy almost to the panicle : 
leaves usually 3. 
With no conspicuous' white margin. 
Leaf-blades glabrous on both surfaces. 
Spikelets barely exceeding 1 mm. 
long, obovoid : primary leaf- 
blades 5-7 cm. long. 
Spikelets 1.5 mm. long, elliptic : pri- 
mary leaf-blades usually less 
than 5 cm. long. 
Leaf-blades pubescent, at least below. 
Stems very slender, weak : stem- 
leaves light green, thin, spread- 
ing, usually less than 2 cm. long. 
Upper surface of the blades pubes- 
cent with very long weak 
hairs. 
Upper surface of the blades gla- 
brous. 
Stem stouter: stem-leaves grayish 
green, firm, 2-3 cm. long. 
Ligule of hairs 2-4 mm. long. 

Leaf-blades glabrous on the lower surface. 
Plant bright green : panicle broadly ovoid, 

its branches spreading. 
Plant grayish green, the leaves purplish : 
panicle oblong, its branches ascend- 
ing or nearly erect. 
Leaf-blades pubescent beneath with short 
hairs. 
Stems slender, glabrous. 

Plant bright green : sheath margin cili- 

ate with long hairs. 
Plant grayish green: sheath margin 
naked. 
Stems rather stout, the lower portion 
densely pubescent with long nearly 
erect hairs. 
^gJSpikelets exceeding 2 mm. in length. 

Primary leaf-blades elongated, broadly linear, often 

2 dm. long and 1.5 cm. wide, spreading. 
Primary leaf-blades lanceolate : 
Rounded or truncate at the base. 

Margins ciliate, at least for the lower half. 
Margins naked, or sometimes Avith a few hairs 
at the ver>- base. 
Leaf-blades spreading : first scale )^ as Ion 
as the spikelet, acute. 
Stems puberulent : primarj^ leaf-blades 
less than 4 cm. long: plant usually 
purplish. 

Stems glabrous : primary leaf-blades 5-7 
cm. long: plant usually green. 
Leaf-blades erect : lirst scale '^i-% as long as 
the spikelet, rounded at the apex. 
Cordate at the clasping base. 

Leaf-blades glabrous, sometimes ciliate on the 
margins. 

Stems puberulent : blades naked on the 

margin. 
Stems glabrous : blades ciliate on the margin. 
Leaf-blades pubescent. 
ft Leaf-sheaths pubescent with long hairs. 

Spikelets verj- strongly and sharply nerved, acute: leaf-blades 
elongated, broadly linear or linear-lanceolate, the larger 
ones often 2 dm. long anvl 1 cm. wide. 



67. P. WrightiauKm. 






1)1. /*. erect ifoliinn. 



89. P. sphaerocarpon. 



90. P. in flat uw. 



73. P. albomarf/hiatunu 

74. P. tnfolium. 



71. P. gracilicaule. 



72. P.flavovirens, 



70. P. Cuthbertu. 
69. P. ensifoliuvi. 
lb. P. glahnssii/nnu 



81. P. nitldiun. 



11. P. pauci})lliun 



81. P. nitidum. 

76. P. longiUgulatnm 



80. P. parvispicultim 



107. P. equilateralf. 



52. P. Xashianum. 



53. P. pateiitifolittm. 
101. P. epilifoHum. 

54. P. Webba-ianum 



108. P. Ashei. 

111. P. eomniutatum. 

109. P. ovale. 



105. P. scabiHtiscnlum 



POACEAE 



89 



Spikelets and leaf-blades not as above, the former obtuse. 
Spikelets glabrous, or with a few scattered hairs. 
Spikelets 3 mm. long. 

Leaf-sheaths, at least the lower ones and those on the 

branches, densely papillose-hispid. 
Lower leaf-sheaths wi'th scattered papillae from some of 
• which arise hairs. 
Spikelets not exceeding 1.5 mm. long. 

Leaf-blades pubescent with long weak liairs. 
Leaf-blades glabrous, or if pubescent the hairs few and 
very short. 
Spikelets densely pubescent. 

Leaf-blades glabrous on both surfaces, or the lower surface 
sometimes with a few scattered long hairs. 
Spikelets 2 mm. long or less. 

Leaf-blades oblong-lanceolate, broadest at the mi<l- 

dle : spikelets al)out 1.5 mm. long. 
Leaf-blades broadest below the middle, long-acumi- 
nate ; spikelets a little less than 2 mm. long. 
Spikelets about 3 mm. .long : 
Broadly obovoid, turgid. 
Elliptic, not turgid. 
Leaf-blades pubescent on one or both surfaces. 

Spikelets but little exceeding 1.5 mm. long or less. 

Lower surface of the leaf-blades softly pubescent with 
usually short hairs, sometimes intermixed with a 
few stiff ones. 

Spikelets about 1 mm. long. 
Spikelets about 1.5 mm. long. 

Upper surface of the leaf-blades glabrous or 
nearly so, or at first with a few scattered 
hairs. 
Leaf-blades conspicuously ciliate on the 

margin with long hairs. 
Leaf-blades naked on the margin, or some- 
times with a few scattered hairs. 
Upper surface of the leaf-blades strongly pubes- 
cent, sometimes with long stiff hairs. 
Stems low, slender, usually 2 dm. tall or less. 
Stems tall, stout, 4 dm. high or more. 

Spikelets obovoid, 1.5 mm. long: pubes- 
cence on the lower surface of the leaf- 
blades short. 
Spikelets elliptic, about 1.75 mm. long: 
pubescence on the lower surface of 
the leaf-blades longer and villous. 
Lower surface of the leaf-blades as w^ell as the upper 
surface pubescent with long usually stiff hairs. 
Spikelets 2 mm. long or more. 

Pubescence on the lower surface of the leaf-blades of 
long stiff spreading hairs. 
Pubescence on the leaf-sheaths and stems appressed 

or ascending. 
Pubescence on the sheaths and stems widely 
spreading. 
SpiKelets about 2 mm. long, obovoid. 

Hairs on the upper surface of the leaf-blades 

similar to those on the lower surface. 
Hairs on the upper surface of the leaf-blades 
much longer than those of the lower . 

surface. 
Spikelets 2.5-2.75 mm. long, elliptic. 
Spikelets purplish. 
Spikelets yellow. 
Pubescence on the lower surface of the leaf-blades of 
either soft and short or appressed hairs. 
Upper surface of the leaf-blades glabrous, or at 
least the put>escence much more scanty than 
on the lower surface. 
Stems pubescent below with long stiff appressed 
or nearly appressed hairs. 
Leaf-blades naked on the margins : 

Exceeding 1 cm. in width : spikelets about 

4 mm. long. 
Less than 1 cm. in width : spikelets 3 mm. 

long or less. 
Spikelets 2-2.5 mm. long. 
Spikelets 3 mm. long. 
Leaf-blades ciliate on the margin with long 
hairs. 
Stems villous below. 
Both surfaces of the leaf-blades pubescent with 

short hairs. 
Stems glabrous or nearly so. 
Stems strongly pubescent. 

Pu)>escence minutely villous, or of long and 
stiff ascending or appressed hairs. 



118. P. Scrilmrrianum 
1(M. P. Ildkri, 

61. P. Earlci. 

64. P. curtlfoUum. 



88. P. Lindhfimcri. 

50. P. armicoln, 

118. P. Scrihnena nnm 
104. P. lldleri. 



79. P. leucothiHx. 



83. P. ciUosHiii. 
82. P. Tainci<seens( 



86. P. flliculine. 



84. P. lanvf/inosnvu 



85. P. ThurminL 
87. P. unciphyUum 



93. P. chrysopsidi/olmm. 



94, P. pseudopitbescens 



95. P, Atfmiticum. 

96. P. villoaissimum. 

97. P. xanthospeniium 



119. P. RavrneliL 



98. P.Commondanum, 

99. P. dricti folium, 

100. P. ciliiferum, 
117. P. olf(70f*an(heii. 



GO. P. annulum. 



90 



POACEAE 



9'2. P. polijunthes. 



F 

Plant ^reen : stems slender : leaf-blades 

rather sparingly pubescent. 10*2. i\ pedicellatatn. 

Plant purplish : stems stout : leaf-blades 

densely pubescent. 103. P. malacon. 

Pubescence of widely spreading- hairs. 

Stems, as well as the leaf-sheaths, densely 
velvety pubescent, usually 6-8 dm. 
tall. 106. P, acopariam. 

Stems, as well as the leaf-sheaths, papil- 
lose pubescent with rather stiff long 

hairs, usually less than 4 dm. tall. 115. 7*. malocophylhun 

** Middle leaf-blades of the main stem more than 1.5 cm. wide, some- 
times 3-4 cm. in width, the base cordate and clasping. 
Spikelets 3 mm. long or less. 

Leaf-blades glabrous, or sometimes ciliate on the margins. 
Spikelets 1.5 mm. long. 
Spikelets 2-3 mm, long. 

Leaf-sheaths glabrous, or sometimes ciliate on the margin. 
Basal leaf-blades smaller than those of the stem. 

Stems erect, even in the late state, sparingly branched: 

spikelets obtuse or acutish. 111. P. commutatum. 

Stems finally much-branched and prostrate, forming 

large mats : spikelets very acute. 110. P. Manatense. 

Basal leaf-blades usually very long, larger than those of 
the stem : 
Their margin naked. 113. P. JooriL 

Their margin ciliate with long hairs. 112. P. tmitabile. 

Leaf-sheaths, at least the lower ones and those of the 

branches, densely papillose-hispid. 114. P. clamlestinum 

Leaf-blades pubescent : 

Ovate-lanceolate: stems pubescent with short ascending 

hairs. 
Linear: stems densely velvety pubescent with spreading 
hairs. 
Spikelets exceeding 3 mm. long. 

Pubescence on the stem and leaf-sheaths, if any, of soft weak 
hairs. 
Nodes naked: leaf-blades usually ciliate on the margin. 120. P. macroearpon 

Nodes densely barbed with spreading hairs: leaf-blades usu- 
ally naked on the margins. 
Lower surface of the leaf-blades paler, glabrous. 121. P. Porterianam. 

Lower surface of the leaf-blades pubescent, as are also the 
sheaths and stems. 
Pubescence on the stem and leaf-sheaths of coarse rigid hairs 

arising from manifest papillae. 119. P. EaveneUL 

IX. LATIFOLIA. 



109. P. ovale. 
106. P. scoparium. 



122. P. puhifoUum 



Tropical plants represented in our range "by a single species. 123. P. laHfolium. 

1. Panlcum prostratum Lam. Stems prostrate and creeping, leafy, branching, the 
summit ascending : leaf-blades ovate, glabrous or pubescent, ciliate on the margin near the 
cordate-clasping base, usually 1-3 cm. long, sometimes larger : racemes 4-6, ascending, 
one-sided, 1.5-2.5 cm. long : spikelets about 2 mm. long, elliptic, glabrous, acute, the first 
scale broader than long, truncate at the apex, the fourth scale transversely rugose. 

Along roadsides, Louisiana. Introduced from tropical countries. Summer and fall. 

2. Panlcum obtusum H.B.K. Glabrous. Stems erect, simple, or branching at the 
base, 3-6 dm. tall : leaf-blades usually erect, long-acuminate, 6-22 cm, long, 2-6 ram. wide: 
panicle linear, 5-15 cm. long, its brandies appressed, one-sided : spikelets about 3 mm. long, 
crowded, oval or obovoid, obtuse, turgid, in pairs, the one short- the other long-pedicelled, 
glabrous, the first scale shorter than the rest, 5-nerved. 

In dry usually sandy places, Kansas and Colorado to Texas and Arizona, Also in Mexico. Sum- 
mer and fall. 

3. Panlcum moUe Sw. Sterile stems 1-2 m. long, rooting at the nodes, the fertile 
stems erect, 6-10 dm. tall or more, the nodes densely barbed : leaf-sheaths often overlap- 
ping, papillose-hirsute : blades 1-3 dm. long, glabrous or pubescent, 7-15 mm. wide : 
panicle 1.5-2 dm. long, its branches spreading or ascending : spikelets about 3 mm. long, 
glabrous. 

In fields and along roadsides, Florida to Texas. Introduced from tropical America. Summer 
and fall. 

4. Panicuin paspaloides Pers. Aquatic. Stems 6-12 dm. long, usually clothed with 
sheaths below : leaves glabrous ; blades 2.5 dm. long or less, 6-10 mm. Avide : racemes 
10-20, one-sided, the rachis broadly winged, appressed, 2-3.5 cm. long : spikelets about 2.5 
mm. long, ovate, acute, glabrous, singly disposed in 2 rows, the first scale broader than 
long and clasping the spikelet at its base, truncate at the apex, the fourth scale transversely 

wrinkled. 

In shallow water, southern Florida and Texas. Also in tropical America, Asia and Australia 
Spring to fall. Water Grass. 



<^ 



4 



POACEAE 



91 



5. Panicum digitarioides Carpenter. Aquatic. Stems from stout rootstocks, 6-12 
dm. tall or more : leaves glabrous ; blades 3 dm. long or less, 6-12 mm. wide : racemes 
6-20, appressedj one-sided, 4-10 cm. long, the rachis barely if at all winged : spikelets in 
pairs, the one short- the other longer-pedicelled, about 2.5 mm. long, the scales promi- 
nently nerved, the first scale ovate, acute, the fourth scale smooth. 

In shallow water, Delaware to Florida and Texas. Spring and summer. 

6. Panicum ciltatissimutn Buckl. Perennial. Stems slender, branched at the base 
and barbed at the nodes, 2-6 dm. long : leaf-sheaths pubescent ; blades 4-9 cm. long, 3-5 
mm. wide, flat, sparingly pubescent beneath and usually long-ciliate on tlie margin near 
the base : panicle 4-6 cm. long, its branches erect : spikelets about 4 mm. long, ovoid, the 
first scale deltoid-cuneate, but little shorter than the spikelet, glabrous, the second scale 
pubescent, the hairs near the margin very long, the third scale pubescent near the margni 
with very long hairs. 

In low grounds, southern Texas. Spring and summer. Indian Wheat. Carpet Grass. 

7. Panicum fus'cum Sw. Annual. Stems tufted, finally branching at the base and 
often rooting at the lower nodes, glabrous, 3-8 dm. long : leaf-sheaths glabrous, pubescent ; 






blades 2.5 dm. long or less, 8-20 mm. wide, glabrous or pubescent : panicle 1-2 dm. Ion 
its branches ascending or nearly erect : spikelets usually borne in pairs on one side of 
the branches on fre(iuently bristle-bearing pedicels, brown or green, 2.5-3 mm. long, 
broadly obovoid, turgid, glabrous, obtuse, the second and third scales witli anastomosing 
veinlets, the fourth scale transversely rugose. 

In various situations, southern Florida and Texas. Also in tropical America. Spring to fall. 

8. Panicum fascicul^tum Sw\ Annual. Stems 4-6 dm. tall, glabrous, branching 
below : leaf-sheaths glabrous; blades 2 dm. long or less, 1.5-2 cm. wide, glabrous: pan- 
icle 1-2 dm. long, its branches ascending or nearly erect : spikelets usually borne in pairs 
on one side of the branches, green, glabrous or pubescent, oval, abruptly acuminate, about 
4 mm. long, the second and third scales with a few anastomosing veinlets, the fourth scale 
transversely rugose. 

In sandy soil, Key West. Also in the West Indies. Spring to fall. 

9. Panicum Tex^num Buckl. A softly pubescent annual. Stems 3-8 dm. tall, leafy, 
often branched at the base : leaf -blades erect, lanceolate, acuminate, conmionly 1-2 dm. 
long, 1-2 cm. wude : racemes usually 6-12, erect, one-sided, 3-8 cm. long, the racliis -wing- 
less : spikelets in pairs, 5-6 mm. long, ovate, acute, pubescent, one short- the other longer- 
pedicelled, the pedicels bristly, the first scale more than i as long as the spikelet, ovale, 
acute, the fourth scale transversely rugose. 

On plains and prairies, Texas. Summer and fall. Texas Millet. 

10. Panicum Chapindnil Vasey. Glabrous or nearly so. Stems 3-6 dm. tall, 
slender, sometimes branched below : leaf -blades 3 dm. long or less, 4-6^ mm. wide, long- 
acuminate : inflorescence 1.5-2.5 dm. long, composed of appressed one-sided racemes, tlie 
lower ones 3-5 cm, long, the rachis terminating in an awn-like point : spikelets nearly 
sessile, 2 mm. long, singly disposed in 2 rows, broadly obovoid, glabrous, the fourth sci)le 
finely transversely rugose when mature. 

In sandy soil, Florida keys. Summer. 

11. Panicum ramis^tum Scribn, Glabrous. Stems from a stout rootstock, 2-6 
dm. tall, simple : leaf-blades ascending, 4^12 cm. long, 2-4 mm. wide : panicle narrow, 
4-10 cm. long, its short branches appressed and terminating in an aM'n-like projection : 
spikelets about 2.5 mm. long, the fourth scale transversely rugose. [P. subspicatam A'asey, 

not Desv.] 

In sandy places, southern Texas. Spring and summer. 

12. Panicum Reverchonii Vasey. Glabrous. Stems from a stout rootstock; 2-4 



dm. tall, simple : leaf-blades erect, usually involute in drying, 1-2 dm. long, 2-4 mm 
wide : panicle narrow, 6-12 cm. long, its short branches appressed and terminating in an 
awn-like projection : spikelets 3.5 mm. long, glabrous, the fourth scale finely and trans- 
versely rugose at maturity. 

On sandy plains, Texas. Spring and summer. 

13. Pan«cum verrucosum Muhl. Stems erect or decumbent, slender, generally 
much branched at the base : leaf-sheaths glabrous ; blades 5-18 cm. long, 2-8 mm. wide, 
erect or ascending, glabrous : panicle 7-30 cm. long, its lower brandies 5-15 cm. long, 
naked below : spikelets about 1.5 mm. long, elliptic, acutish. 

In moist or wet soil, Massachusetts to F'lorida and Louisiana. Spring to fall. 

14. Panicum brachydnthum Steud. Glabrous. Stems at first erect, finally prostrate 
at theba.se and branching, and rooting at the lower nodes, sometimes 1 m. long: leaf-sheaths 
shorter than the internodes ; blades erect or nearly so, usually 1.5 ilm. long or less, 2-3 mm. 



92 



rOACEAE 



wide, linear: panicle 6-14 cm. long, its branches very long, naked below, erect to Avidely 
spreading: spikelets at the end of the branches, 3-4 mm. long and 1.5-1.8 mm. wide, 
elliptic, acute, densely papillose-hirsute with ascending hairs. [P. sparsiflormn Vasey.] 

In wet soil, the Indian Territory to Mississippi and Texas. Fall. 

15. Panicum capillare L. Stems 3-6 dm. tall, simple, or branched near the base, 
stout: leaf-sheatLs usually purplish, papillose-hirsute; blades 1.5-8 dm. long, 6-16 mm. 
wide, pubescent: primary panicle 2-3.5 dm. long, the larger branches 1,5-2.5 dm. long, 
the lateral panicles smaller : spikelets very numerous, 2-2.5 mm. long, lanceolate, acumi- 
nate, glabrous. 

In dry soil, and common in cnltivated ground as a weed, Xova Scotia to Minnesota, Florida and 
Texas. Summer and fall. Witch Grass. Tumble Weed. 

16. Panicum Philadelphicum Bernh. Stems erect, 2-6 dm. tall, slender, somewhat 
branclied at the base : leaf-sheaths hirsute ; blades 5-10 cm. long, 2-6 mm. wide, erect, 
pubescent : panicle 10-23 cm. long, its lower branches spreading or ascending : spikelets 
about 1.5 mm. long, elliptic, acute, glabrous. 

In dry woods and thickets, New Brunswick to Georgia and Missouri. Summer and fall, 

17- Panicum Gattingeri Xash. Annual. Stems commonly slender, finally branched 
and often prostrate at the base, 3-6 dm. long: leaf-sheaths papillose-hirsute; blades 1.5 
dm. long or less, 4-8 mm. wide, pubescent, erect: primary panicle 1-1.5 dm. long, its 
branches ascending, the larger ones usually 5-7 cm. long, the lateral panicles smaller : 
spikelets about 2 mm. long, elliptic, acute, glabrous. 

In f»oor soil, Connecticut and New Jersey to North Carolina and Tennessee ; also in Missouri. Fall. 

18. Panicum flexile (Gattinger) Scribn. Stems erect, 1.5-4.5 dm. tall, slender: 
leaf-sheaths papillose-hirsute ; blades 10-23 cm. long, 4-6 mm. wide, erect, long-acumi- 
nate, pubescent : panicle 1-2.5 dm. long : spikelets about 3 mm. long, much shorter than 
the pedicels, acuminate, glabrous. 

In moist or dry soil, Pennsylvania to Tennessee and Missouri. Summer and fall. 

19. Paniciim proliferum Lam. Stems at first erect, 3-6 dm. tall, simple, later de- 
cumbent, 1-1.5 m. long, branched at all the upper nodes : leaf -sheaths loose, glabrous, 
somewhat flattened ; blades 1.5-6 dm. long, 4-20 mm. wide, long-acuminate : panicle 
pyramidal, 1-4 dm. long : spikelets 2-3 mm. long, lanceolate, acute, glabrous. 

In wet soil, Maine to Pennsylvania, Nebraska, Florida and Texas. Summer and fall. 

20. Panicum mili^ceum L. Stems erect or decumbent, rather stout, 3 dm. tall or 
more : leaf-sheaths papillose-hirsute ; blades 1-2.5 dm. long, 8-25 mm. wide, pubescent : 
panicle rather dense, 1-2.5 dm. long, its branches erect or ascending ; spikelets 5 mm. long, 
acuminate, glabrous. 

In waste places, Maine to Delaware, Pennsylvania, and Georgia, and in Nebraska. Introduced 
from the Old World. Summer and fall. Millet.' 

21. Panicum stenodes Griseb, Glabrous, or the lower leaf-sheaths sometimes 
pubescent. Stems tufted, wiry, erect, 3-8 dm. tall, finally branched : leaf-blades erect, 
involute when dry, 1.5 dm. long or less, 1-1.5 mm, wide : panicle narrow, 3-15 cm. long, 
its branches erect, the pedicels often with a few bristles at the base : spikelets about 2.5 
mm. long, lanceolate, acute, glabrous. 

In moist and sandy pine lands, Florida to Texas. Also in the West Indies. Spring to fall. 

22. Panicum diffusiim Sw. Glabrous. Stems tufted, erect, 2-4 dm. tall, rather 
slender: leaf-blades linear, nari'owed toward the base, long-acuminate, 2.5 dm. long or 
less, 3-4 mm. wide, erect : panicle 8-15 cm. long, its branches ascending : spikelets gla- 
brous, lanceolate, acute, aboiit 2 mm. long. 

In sandy soil, southern Texas and Mexico. Spring to fall. 

23. Panicmn Hdllii Vasey. Stems tufted, branching from the base, glabrous : leaf- 
sheaths glabrous ; blades erect, linear, long-acuminate, 5-15 cm. long, 2-4 mm. wide, gla- 
brous : panicle 1-2 dm. long, its branches long and ascending: spikelets about 2.5 mm. 
long, ovoid, acute, glabrous. 

In dry soil, Texas. Spring and summer. 

24. Panicum filipes Scribn. Glabrous. Stems erect, 8-10 dm. tall: leaf-blades 
linear, long-acuminate, lighter above, 3-4 dm. long, 5-8 mm. wide : panicle 1.5-2.5 dm. 
long, effuse, its slender branches spreading : spikelets glabrous, ovate-lanceolate, about 
2.5 mm. long, acute, the first scale large and acute, a little more than | as long as the 
spikelet. 

In dry soil, southern Texas. Spring and summer. 

25. Panicum cognatum Schult. Stems tufted, 3-6 dm. long, at first erect, finally 
prostrate and branched at the base, glabrous : leaf -sheaths usually longer than the inter- 
nodes, glabrous, or more or less pubescent with very long weak hairs ; blades erect, linear 



POACEAE 



93 



to linear-lanceolate, glabrous, or sometimes pubescent, the primary ones 3-8 cm. long, 4-7 
mm. wide, those on the branches smaller : panicle at first included at the base, finally ex- 
serted, as broad as or broader tlian long, the branches very long and finally spreading : 
spikelets on pedicels many times their length, elliptic, 2.5-3 mm. long and about 0.8 mm. 
wide, glabrous or pubescent. [P. autumnale Bosc] 

In dr>' places, South Carolina to Minnesota, Florida, Texas and Arizona. Spring and fall. 

26. Panicum capillarioides Vasey. Perennial. Stems tufted, erect, or geniculate 
at the base, pubescent with spreading hairs, at least below : leaf-blades erect or ascending, 
linear, glabrous, or sparingly pubescent, 2 dm. long or less, 3-5 mm. wide : panicle 1-1.5 
dm. long, its branches long and ascending : spikelets lanceolate, acuminate, 6 mm. long, 
glabrous. 

In dry soil, southern Texas. Summer. 

27. Panicum haldphilum Nash. Stems from a long stout rootstock, 1.5-4 dm. tall : 
leaves numerous, crowded at the base of the stem ; sheaths overlapping, the margins some- 
times ciliate ; blades spreading, lanceolate, usually 2-6 cm. long, sometimes longer, 3-8 
mm. wide : panicle dense, 2-9 cm. long, its branches ascending : spikelets crowded, gla- 
brous, about 2.5 mm. long, the first scale 2 as long as the spikelet, or nearly bo, the apex 
acute at a broad angle, apiculate. 

In sand along the seashore, Mississippi. Also in Mexico. Spring to fall. 

28. Panicum ripens L. Stems 3-8 dm. tall, from long stout rootstocks : leaf -sheaths 
overlapping, at least at the base, the lower ones at first densely hirsute, later sometimes 
glabrate ; blades erect to spreading, 1.5 dm. long or less, 3-6 mm. wide : panicle 6-15 cm. 
long, narrow and confined, slender, its branches erect or ascending : spikelets yellowish or 
green, glabrous, 2.5 mm. long, the first scale about } as long as the spikelet, truncate at 
the apex. 

In sand along the seashore, Alabama, Mississippi, and California. Of wide geographic distribu- 
tion. Summer and fall. 

29. Panicum amarum Ell. Smooth and glabrous, glaucous. Stems arising from long 
branching rootstocks, 3-9 dm. tall : leaf-sheaths overlapping ; blades 1.5-3 dm. long, 6-12 
mm. wide, long-acuminate, thick and leathery, involute on the margins, at least toward 
the apex : panicle linear, less than 3 dm. long, its branches erect : spikelets 5-6 mm long. 

On sea beaches, Xew Hampshire to Florida. Fall. 

30. Panicum virgatum L. Glabrous. Stems erect from a stout rootstock, 9-15 
dm. tall : leaf-blades elongated, 3 dm. long or more, 6-12 mm. wide, flat, glabrous or pu- 
bescent : panicle 1.5-5 dm. long, its branches widely spreading or sometimes nearly erect : 
spikelets ovate, acuminate, 4-4.5 mm. long, glabrous. 

In moist or dry soil, Maine and Ontario to Minnesota, Florida and Texas. Summer and fall. A 
variety, known as A virgatum hreviramosum Nash, with short spreading branches and smaller spikelets, 
occurs in eastern Georgia. Switch Grass. 

31. Panicum minimum Jacq. Stem 1-2 m. tall or more, leafy : leaf-sheaths over- 
lapping, glabrous, or tuberculate-pubescent ; blades 2-8 dm. long or more, 1-4 cm. wide, 
glabrous : panicle 3-6 dm. long, its branches erect or nearly so, very long : spikelets gla- 
brous, 3-4 mm. long, the fourth scale transversely rugose. 

In fields and along roadsides, Georgia and Florida to Texas. Introduced from tropical America. 
Summer and fall. 

32. Panicum agrostoides Muhl, Stems 4-8 dm. tall, much branched, compressed : 
leaf-blades 3 dm. long or more, 4-8 mm. wide : panicle pyramidal, 1-3 dm. long, its 
branches spreading : spikelets 1.5-2 mm. long, acute, straight. 

In wet ground, Maine to Missouri, Florida and Texas. Summer and fall. 

33. Panicum cond6nsum Nash. Stems 6-10 dm. tall, branched, the lateral panicles 
often much exserted : leaf-blades 2-4 dm. long, 6-8 ram. wide, erect : panicle dense, 1-2 
dm. long, contracted, its branches erect : spikelets numerous, about 2 mm. long, glabrous, 
acute. 

In ditches and wet places, South Carolina to Florida. Fall. 

34. Panicum Combsii Scribn. & Ball. Glabrous. Stems tufted, erect, slender, finally 



branched, 4-6 dm. tall : leaf-sheaths compressed, keeled ; blades erect, linear, acuminate, 
5-15 cm. long, 2-3 mm. wide : panicle about 1 dm. long, its branches finally spreading : 
spikelets 3 mm. long, lanceolate, acute. 

In damp or wet woods, Florida. Summer and fall. 

35. Panicum pseuddnceps Nash, Glabrous. Stems tufted, 3-7 dm. tall, erect, 
slender, compressed, finally branching at each node : leaf-sheaths compressed and keeled, 
an external tuft of long Jiairs on each side at the apex ; ligule a ring of hairs 2-3 ram. 
long ; blades 1-3 dm. long, 2-4 mm. wide, somewhat pilose on the upi>er surface nejir the 



94 



POACEAE 



base : panicle narrow, 1-2 dm. long, its slender brandies erect : spikelets numerous, about 
2.0 nmi. long, lanceolate, often with 1-3 bristles at the base, glabrous. 

In pine lands, southern i>eninsular Florida. Summer and fall. 

36. Panicum stipitatum Nash. Stems erect, 9-15 dm. tall, much branched : leaf- 
blades 3 dm. long or more, 4-8 mm. wide, acuminate, rough : panicle pyramidal, 1-3 dm, 
long, its primary bi-anclies spreading or ascending: spikelets about 2.5 mm. long, acumi- 
nate, the fourth scale on a delicate stalk about 0.5 mm. long. 

In moist soil, New Jersey and Pennsylvania to Kentucky, Tennessee and Georgia. Summer 
and fall. 

37. Panicum rostt^tum Muhl. Stems erect, 4-15 dm. tall, branched : leaf -sheaths 
glabrous, or pubescent ; blades 3 dm. long or more, 4-10 mm. wide : panicles 1.5-3 dm. 
long, its branches erect to spreading : spikelets 2.5-3.5 mm. long, lanceolate, acuminate, 
curved at the apex. 

In moist soil, southern New York and New Jersey to Missouri and the Indian Territory, Florida 
and Texas. Summer and fall. 

38- Panicum linearifolium Scribn. Stems tufted, slender, erect, glabrous, simple, 
1.5-4 dm. tall : leaf-sheaths glabrous or hirsute ; blades glabrous or pvibescent, elongated, 
7-25 cm. long, 2-4 mm. wide, the uppermost blade the longest and often extending beyond 
the panicle : primary panicle loose and open, 4-10 cm. long, its branches ascending : spike- 
lets 2-2.5 mm. long, obtuse or acutish, pubescent with spreading hairs. 

In dry soil, esnecially on hillsides, New York and New Jersey to Missouri and the Indian Terri- 
tory. Summer and fall. 

■ 39. Panicum perlongiim Nash. A tufted pubescent perennial. Stems 2-4 dm. 

tall, simple, glabrous, or sparingly pubescent, the nodes barbed, finally with short basal 

stems : leaves 1 or 2 ; sheaths hirsute with long ascending hairs ; blades elongated, linear, 

erect, papillose-hispid beneath, 2-3 mm. wide, the upper blade commonly 8-14 cm. long : 

panicle much exserted, generally extending beyond the apex of the upper leaf-blade, 4-6 

cm. long, its branches erect or erect-ascending : spikelets about 3.25 mm. long and 1.5-1.75 

mm. wide, pubescent with a few scattered long hairs. 

On prairies and in dry soil, Illinois to South Dakota and the Indian Territory'. Spring and sum- 
mer. 

40. Panicum depauper^tum Muhl. Stems erect, 3 dm, tall or less, simple : leaf- 
sheaths glabrous to hirsute ; blades 8-15 cm. long, elongated, 1-4 mm. wide, the upper one 
sometimes much exceeding the panicle : primary panicle much exserted, 2-8 cm. long, 
usually linear, its branches erect or nearly so : spikelets 3-4 mm. long, glabrous, acute. 

In dry places, Maine to Minnesota, Florida and Texas. Summer and fall. 

41. Panicum glabrifolium Nash, Glabrous and shining. Stems tufted, 1.5-4 dm. tall, 
erect, rigid, slender, leafy, finally much branched : leaf -sheaths with a tuft of hairs on each 
margin at the apex ; blades narrowly linear, erect, rigid, thickish, long-acuminate, nar- 
rowed toward the base, those on the shoots 1.5 dm. long or less, 3-4 mm. wide, those on 
the flowering stems 3-9 cm, long, 1-3 mm. wide : panicle ovate, 4 6 cm. long, its branches 
spreading or somewhat ascending : spikelets 1.3-1.5 mm. long and 0.7 mm, wide, obovoid. 

In low pine lands, Florida. Summer. 

42. Panicum strigosum Muhl. A tufted densely papillose-hirsute perennial, the 
pubescence spreading. Stems 2-4 dm. tall, simple : leaves 2 or 3 ; sheaths much shorter 
than the intemodes ; blades erect, lanceolate, 2-7 cm. long, 3-10 mm, wide : panicle tnuch 
exserted, 5-8 cm. long, broadly ovate, its branches spreading or somewhat ascending : 
spikelets 1.3-1.5 ram. long and about 0.8 mm. wide, oval, glabrous. 

In dr>" or moist pine lands. North Carolina and Tennessee to Florida. Spring and summer. 

43. Panicum polycaulon Nash. Yellowish green. Stems tnfted, naked above, 2 
dm. tall or less, erect, simple, finally branched : leaf-sheaths ciliate on the margin ; blades 
erect or ascending, narrowly oblong-lanceolate, 2-7 cm. long, 2-8 mm. wide, ciliate on the 
margin : panicle broadly ovate, 3 cm. long or less, its branches spreading or ascending, the 
main axis and generally the branches sparingly pilose : spikelets about 1,5 mm.' long and 
0.8 mm. wide, obovoid, obtuse, glabrous. 

In low pine lands, Florida to Mississippi. Also in Cuba. Summer. 

44. Panicum cili^tum Ell. Stems tufted, 1-2.5 dm. tall, simple, glabrous, the axis 
of the panicle and its branches hirsute : leaves usually 2; sheaths shorter than the inter- 
nodes ; blades spreading or ascending, glabrous on both surfaces, conspicuously ciliate on 
the margins, acute at the apex, some^vhat cordate at the base, narrowly elliptic, linear or 
lanceolate, usually 2-6 cm. long and 5-10 mm. wide, rarely larger : panicle 3-5 cm. long, 
broadly ovate, its branches ascending: spikelets 1.8-2 mm. long and about 1 mm. wide, 
elliptic, pubescent with short spreading hairs, rarely nearly glabrous, the first scale about 
I as long as the spikelet. 

In sandy soil, Xorth Carolina to Florida and Mississippi. Spring and 



POACEAE 



95 



45. Pantcum pyriforme Xash. Stems densely tufted, 3-4 dni. tall, rather slender, 
glabrous, rather weak, fhially nuicli branched : leaves usually 2, or sometimes 3 ; sheaths 
densely papillose-hirsute witli long reflexed hairs ; blades thin, lax, glabrous on both sur- 
faces, long-acuminate, narrowed to the barely rounded base, the primary ones 1-2 dm. 
long, 8-12 mm. wide: panicle ample, loose and open, 6-11 cm. long, its branches widely 
spreading: spikelets rather few, al)out 2.5 mm, long and 1.5 mm. wide, broadly obovoid, 
densely pubescent with long hairs. 

In clay or sandy soil, peninsular Florida. Spring and summer. 

46. Panicum laxiflorum Lam. Stems tufted, erect, simple, 2-4 dm. tall, pubescent 
or glabrous : leaf-sheaths hirsute with reflexed hairs ; blades 6-13 cm. long, 4-10 nun. 
wide, erect, glabrous or pubescent, ciliate on the margin : panicbe 5-10 cm. long, its axis 
and erect or spreading branches sometimes hirsute : spikelets about 2 mm. long, elliptic or 
narrowly obovoid, strongly pubescent. 

In moist or dry soil, Virginia to Kentucky and Florida. Summer. 

47. Panicum neurdnthum Griseb. A tufted usually glabrous perennial, or some- 
times the sheaths and lower part of the stem ascending-hirsute. Stems erect, 3-6 dm. tall, 
finally dichotoraously much-branched : primary leaves 4-6 ; sheaths usually much shorter 
than the internodes ; blades erect, firm, thickish, the primary ones 3-10 cm. long, 2-5 mm. 
wide, long-acuminate, those on the branches much smaller and usually involute : primary 
panicle much exserted, narrow, 5-8 cm. long, its branches erect or nearly so, sometimes 
spreading in age : spikelets 1.75-2 mm. long and about 1 mm. wide, turgid, broadly obo- 
void, pubescent Avith short spreading hairs. [P. ovinum Scribn. & Smith.] 

In dry or moist sandy soil, Virginia to Florida, Texas and the Indian Territory. Also in Cuba. 
Spring to fall. 

r 

48. Panicum angustifolium Ell. Stems tufted, 3-6 dm. tall, finally profusely 
branched, glabrous, or sometimes pubescent toward the base : primary leaves usually 4 or 
5 ; sheaths glabrous, or the lower ones sometimes pubescent ; blades erect, linear-lanceolate, 
acuminate, glabrous, or the lower ones sometimes pubescent below, ciliate on the margin 
near the base, 5-12 cm. long, 3-6 mm. wide, those on the branches much smaller, crowded, 
usually involute : primary panicle broadly ovate, long-exserted, 6-9 cm. long, its branches 
spreading, glabrous, the secondary panicles much smaller, simple or nearly so : spikelets 
obovoid, 2.5-3.5 mm. long and 1.3-1.6 mm. broad, strongly nerved, densely pubescent with 
spreading hairs. [P. arenicoloides Ashe. P. orihophyllum Ashe,] 

In dry sandy soil, Maryland to Florida and Texas. Spring to fall. 

49. Panicum consanguineum Kunth. A densely villous tufted perennial. Stems 
3-7 dm. tall, finally much branched, the nodes barbed with spreading hairs : primaiy leaves 
usually about 5 ; sheaths shorter than the internodes ; blades erect, linear-lanceolate, the 
primary ones 4-8 cm. long, 3-10 mm. wide, those on the branches much smaller : primary 
panicle 4-8 cm. long, oval, its branches ascending: spikelets 2.5 mm. long and about 1.3 
mm. wide, broadly obovoid, densely pubescent with spreading hairs. 

In dry sandy soil. North Carolina to Florida and Texas. Spring and summer. 

50. Panicum arenicola Ashe. Stems tufted, erect, usually from an ascending base, 



2-4 dm. tall, finally branched, pubescent below with long ascending or nearly erect hairs 
minutely pubescent above : leaves 4 or 5, confined to the lower two-thirds of the stem ; 
sheaths, at least the lower ones, hispid with ascending hairs ; blades^ erect, firm, stiff, in- 
clined to become involute in drying, acuminate from below the middle, the lower ones 
sparingly hispid beneath, 2-6 cm. long, 2-6 mm. wide: panicle. long-exserted, broadly 
ovate, 2-5 cm. long, its branches widely spreading : spikelets a little less than 2 mm. long 
and about 1.2 mm. wide, broadly obovoid, pubescent with very short spreading hairs. 

In drj' soil, North Carolina to Mississippi. Summer. 

51. Panicum Roanok^nse Ashe. Glabrous. Stems tufted, erect, 3-6 dm. tall, 
finally branched : leaves 3 or 4 ; blades erect, rather firm, 3-8 cm. long, 3-5 mm. wide : 
panicle 5-7 cm. long, its branches ascending : spikelets glabrous, 2 mm, long and 1 mm. 
wide, elliptic. 

In dry soil, North Carolina. Summer. 

52. Panicum Nashi^mn Scribn. Stems tufted, glabrous or puberulent, slender, 
1.5-4 dm. tall, finally much branched : leaf-blades erect or ascending, lanceolate, acumi- 
nate, glabrous or puberulent beneath, ciliate, at least at the base, 2-5 cm. long, 2-5 mm. 
wide, the l)lades on the branches smaller: primary panicle 2.5-5 cm. long, its branches 
widely spreading : spikelets about 2 mm. long, obovoid, glabrous to densely pubescent with 
short spreading hairs. [P. paucicUiatum Ashe.] 

In piue lands, Virginia to Florida and Mississippi. Spring and summer. 

53. Panicum patentifolium Xash. A nearly glabrous purplish tufted perennial. 
Stems erect or nearly so, 2-4 dm. tall. pnbernlent,'slender, finally much bnmched : leaves 2-4, 



96 



POACEAE 



rather distant ; sheaths muiutely pubescentj especially at the apex on the margins ; blades 
widely spreading, firm, lanceolate, 2,5-4 cm. long, 2-4 nun. wide, puberulent at the very 
base on the npper surface : panicle 4-6 cm, long, broadly ovoid, its axis and spreading 
branches puberulent: spikelets about 2.5 mm. long and 1.3 mm. wide, pubescent with 
spreading hairs, the first scale i as long as the spikelet. 

In dry sandy soil, peninsular Florida. Spring. 

54. Panicum "Webberianum Nash. Stems tufted, 2-4 dm. tall, erect or ascending, 
rigid, branched : leaf-sheaths ciliate on the margin ; blades lanceolate, 4-9 cm. long, 7-14 
mm, wide, sparsely ciliate at the base, usually erect : panicle ovate, 6-9 cm. long, its 
branches spreading: spikelets elliptic or obovoid, 2.5 mm. long and about 1.3 mm. wide, 
the apex of the fourth scale minutely pubescent. [P. Onsloweiise Ashe.] 

In pine lands, North Carolina to Florida. Spring and summer. 

55. Panicum dichdtomum L, Light green, glabrous, or the lower nodes sometimes 
barbed. Stems tufted, slender, 2-6 dm. tall, rarely taller, finally much branched about 
the middle : primary leaves 4 or 5 ; sheaths shorter than the internodes ; blades widely 
spreading, linear-lanceolate, the primary ones 4-8 cm. long, usually 4-8 mm. wide, rarely 
wider, those on the branches much smaller, often involute : panicle 4-8 cm. long, broadly 
ovate, its branches usually ascending : spikelets rather few, 1.75-2 mm. long and 0.8-1 
mm. wide, elliptic, glabrous. 

In dry soil, Connecticut and southern New York to Ohio, Georgia and Texas. Summer. 

56. Panictun ITadkin^nse Ashe. A glabrous perennial. Stems single, 8-10 dm. 
tall, finally somewhat branched : leaves 5 or 6 ; sheaths much shorter than the inter- 
nodes, white-spotted ; blades ascending, lanceolate, acuminate, narrowed toward the base, 
the primary ones 8-12 cm. long, 8-12 mm. wide : panicle 8-12 cm. long, broadly ovate or 
oval, its branches long, ascending : spikelets about 2.3 mm. long and 1 mm. wide, elliptic, 
acute, glabrous. 

In dry or sandy soil, Maryland to Georgia. Summer. 

57. Panicum barbulatum Michx. Glabrous. Stems densely tufted, at first erect, 
finally much branched and decumbent, the nodes strongly barbed with silky somewhat re- 
flexed hairs : primary leaves 5-7 ; sheaths shorter than the internodes, ciliate on the over- 
lapping margin ; primary leaf -blades spreading, sometimes somewhat reflexed, usually 6-10 
cm. long, rarely shorter or longer, 8-15 mm. wide, lanceolate, the blades on the branches 
much smaller : panicle finally much exserted, 7-11 cm. long, oval, its branches ascending : 
spikelets 1.5-1.8 mm. long and about 0.8 mm. broad, elliptic, glabrous, or rarely minutely 
and sparingly pubescent. [P. nitidum var. barbulatum (Michx.) Wood.] 

In wet places, New York to Illinois, Florida and Mississippi. Summer. 

58. Panicum nemopdnthiun Ashe. A tufted nearly glabrous perennial with barbed 
nodes. Stems 3-5 dm. tall, erect : leaves 3 or 4 ; lowermost sheaths sometimes pubescent, 
the uppermost often longer than the internodes ; blades spreading or ascending, lanceolate, 
long-ciliate toward the somewhat narrowed base, 7-10 cm. long, 5-6 mm. wide, long- 
acuminate : panicle 7-10 cm. long, broader than long, its branches wide-spreading, lax and 
drooping : spikelets about 2.5 mm. long, a little exceeding 1 mm. broad, elliptic, glabrous. 

In woods. North Carolina. Spring. 

59. Panicum Mattamuskeet^nse Ashe. A tall sometimes tufted perennial with 
barbed nodes. Stems 6-12 dm. tall, finally much branched : leaves 6 or 7 ; sheaths much 
shorter than the internodes, usually considerably less than \ as long, ciliate on the margins, 
all but the lower ones glabrous ; blades spreading, 3-8 cm. long, 3-10 mm. wide, the lower- 
most pubescent on both surfaces : panicle 6-10 dm. long, ovate : spikelets 2-2.5 mm. long 
and about 1 mm. wide, elliptic, pubescent with short spreading hairs. 

In wet places, North Carolina. Summer. 

60. Panicum dnnnlum Ashe. Stems 4—7 dm. tall, glabrous or sparingly pubescent,, 
finally branched, the nodes densely barbed with spreading hairs: leaves 4 or 5 ; sheaths 
softly pubescent or sometimes the upper ones glabrous ; blades erect or nearly so, softly 
pubescent on both surfaces, or the upper ones sometimes glabrous : panicle 4-10 cm. long, 
its branches erect-ascending or ascending, rarely spreading : spikelets usually numerous,. 
1.8-2 mm. long and about 0.8 mm. wide, elliptic, strongly pubescent with spreading hairs. 

In dry rocky woods, Maryland to Georgia and Mississippi. Spring and summer. 

61. Panicum Edrlei Xash. Stems densely tufted, slender, 1-1.5 dm. tall, usually 
with a few long weak scattered hairs below, finally branched, the nodes rather sparingly 
barbed : leaves about 3 j sheaths rather sparsely hirsute with long hairs ; blades ascending, 
lanceolate, rather sparingly hirsute on both surfaces with long spreading hairs, 1-3 cm.^ 
lono-, 2-6 mm. Avide : panicle 2-3 cm. long, broadly ovate, its smooth branches spreading : 
spikelets about 1.3 mm. long, 0.7 mm. wide, elliptic, glabrous. [P. austromontanum Ashe.} 

In sandy soil, Tennessee and Alabama. Spring and summer. 



POACEAE 



97 



62* Panicum lucidum Aslie, iStejus tufted, 2--8 dm. long, slender, glabrous, weak, at 
iirst erect or ascending, simple, later prostrate and much branched : leaves 3-5 ; sheaths 
much shorter than the internodes, eiliate on the margin ; blades thin, glabrous, the primary 
ones usually erect, 3-6 cm. long, 3-6 mm. wide, those on the brandies mncli smaller, gen- 
erally 3 cm. long or less and 1.5-3 mm. wide, spreading to erect : primary panicle ovoid, 
3-7 cm. long, its branches spreading or somewhat ascending: spikelets "glabrous, 1.5-2 
mm. long and 0.6-0.75 mm. wide, elliptic. 

In wet shady places, usually sphagnum swamps, New Jersev and Maryland to Florida and Missis- 
sippi. Summer and fall. 

63. Panicum curtivaginum Ashe. Stems tufted, 6-8 dm. long, slender, weak, gla- 
brous, finally branched: leaves 4 or 5 ; sheaths much shorter than the intenuKles, some- 
times sparingly eiliate on the margin ; blades erect, glabrous, tlie primary ones linear, 

ally 3-6 cm. long, rarely larger, 3-5 mm. wide : panicle 4-8 cm. long, ovoid, its 
branches ascending : spikelets 2 mm. long and about 1 mm. wide, elliptic, glabrous. 

In sandy soil, Mississippi. Spring and summer. 

64. Panicum curtifoliiun Nash. A nearly glabrous tufted perennial. Stems 2-3 
dm. tall, finally much branched : leaves 3 or 4 ; sheaths usually about J as long as the in- 
ternodes, sparsely pubescent with long weak spreading hairs ; blades widely spreading, 
lanceolate, afew long hairs on the upper surface near the base, the primary blades 1.5-3 cm. 
long, 3-5 mm. wide : panicle 2-4 cm. long, broadly ovoid, its branches widely spread- 
ing : spikelets about 1.5 mm. long and about 0.75 mm. wide, elliptic, glabrous. 

In sandy soil, Mississippi. Spring and summer. 

65. Panicum sphagnicola Nash. Grayish green. Stems 6-10 dm. long, at first 
simple, finally repeatedly and dichotomously branched, the branches very divergent: leaf- 
blades glabrous, thick, lanceolate, the primary ones 5-8 cm. long, 4-10 mm. wide, those 
on the branches 2.5 cm. long or less, 1-3 mm. wide, appressed ; primary panicle about 5 
cm. long, its branches spreading, 1.25-2.5 cm. long, the secondary panicles about 1.25 cm. 
long, raceme-like : spikelets 2.5 mm. long and 1 mm. Avide, few and appressed, glab 
or sparingly pubescent. 

In sphagnum swamps, northern Florida. Summer. 

66. Panicum nudlcaule Vasey. Glabrous. Stems 5-6 dm. tall : leaves 3, the lower 
2 approximate and near the base of the stem, the other distant, above the middle of the 
stem ; blades erect, firm, lanceolate, 2.5-7 cm. long, 3-8 mm. wide : panicle 4-7 cm. long, 
broadly ovate, its branches ascending or spreading : spikelets 3 mm. long and 1 mm. wide, 
elliptic, acute, glabrous. 

In swamps, western Florida. Spring and summer. 

67. Panicum Wrightiinum Scribn. Stems tufted, 3-4 dm. long, puberulent, slen- 
der, at first erect, finally much branched and forming broad mats : leaves 5-7 ; sheaths 
minutely pubescent with spreading hairs, eiliate on the margins ; blades minutely and softly 
pubescent on the lower surface, the upper surface pubescent with longer hairs, the primary 
blades 2-4.5 cm. long, 2-4 mm. wide, those on the branches much smaller : primary panicle 
3-6 cm. long, ovoid, its branches ascending : spikelets a little less than 1 mm. Icmg and 
about 0.4 mm. wide, elliptic, pubescent. 

In sandy soil, North Carolina to Florida and Mississippi. Also in Cuba. Summer and fall. 

68. Panicum B aldwfnii Nutt. Glabrous or nearly so. Stems densely tufted, slender, 
1-2 dm. tall, rarely longer, sometimes a little puberulent, erect, finally much branched and 
ascending or prostrate : leaves on the primary stem 2, or sometimes 3 ; sheaths less than ^ 
as long as the internodes ; blades erect or ascending, lanceolate, rough on the margins, the 
primary ones 1-3 cm. long, 1-3 ram. wide : primary panicle 1.5-4 cm. long, broadly 
ovoid, its branches widely spreading: spikelets 1 mm. long and about 0.7 mm. broad, 
oval, or somewhat broadly ovoid, glabrous. 

In dry sandy soil, southern Georgia and Florida. Spring and summer. 

69. Panicum ensifolium Baldw. A slender much tufted glabrous perennial. Stems 
1-3 dm. tall, finally somewhat branched : leaves 2 or 3 ; sheaths very short, several times 
shorter than the internodes ; blades widely spreading, lanceolate, usually less than 2 cm. 
long, rarely larger, 1-3 mm. wide, densely puberulent on the lower surface, the basal blades 
markedly larger and more erect : panicle small, ovate, 1-2 cm. long, occasionally larger, 
its branches usually ascending : spikelets about 1.3 mm. long and about 0.6 mm. wide, 
elliptic, pubescent with spreading hairs. [P. nitidum var. emifoliiun (Baldw.) Chapm.] 

In sphagnum bogs, North Carolina to Florida and Mississippi. Spring and summer. 

70. Panicum Cuthb6rtii Ashe. Stems tufted, slender, weak, 2-3 dm. tall, glabrotis, 



finally much branched : primary leaves 3 or 4 ; leaf-sheaths short, eiliate on the margin, 
much shorter than the internodes ; blades densely puhc-cent l)eneatli, more sparsely so 

7 






-98 



poacp:ae 



above, with ratliei' long hairs, the primary ones spreading, 1-3 cm. long, l,5-o mm. wide : 
panicle 1.5-3 cm. long, ovate, its branches spreading: spikelets elliptic, about 1.3 mm. 
long and 0.5 mm. wide, pubescent. 

In wet places, South Carolina to Florida. Spring and summer. 

71. Paoicum gracilicaule Xash. Glabrous. Stems tufted, erect, slender, 1-3 dm, 
tall : leaves 3 or 4 ; sheaths shorter than the blades ; blades erect, linear, acuminate, 3-7 
cm. long, 3-8 mm. wide : panicle 3-6 cm. long, ovoid, its branches ascending : spikelets 



about 1.1 mm. long and 0.7 mm. wide, obovoid, pubescent with spreading liairs. 

In sandy soil along brooks, Sand Mountain, Alabama. Summer. 

72. Panicum flavovirens Nash. A glabrous tufted light green perennial. Stems 
2-3 dm. tall, slender, finally much branched : leaves 2 or 3 ; sheaths very short, the lower 
ones ciliate on the margin, the exterior basal ones pubescent all over ; blades thin, erect, 
smooth or nearly so on the margins, linear-lanceolate, the primary ones 2.5-4 cm. long, 2.5 
-4 mm. wide, usually minutely pubescent on the lower surface between the nerves : panicle 
S-4 cm. long, broadly ovate, its branches spreading : spikelets 1.5 mm. long and 0.7 mm. 
wide, elliptic, densely pubescent with spreading hairs, the first scale about ^ as long as the 
spikelet. 

In swampy woods, Florida. Summer. 

73. Panicum albomarginktum Xash, Glabrous, excepting the spikelets. Stems 
densely tufted, 2-4 dm. tall, finally branched toward the base, the upper part of the stem 
naked : leaves usually 2 ; sheaths on the primary stems much shorter than the internodes ; 
blades erect, thick, stiff, lanceolate, with a prominent wide thickened white margin, usually 
1.5-4 cm. long, rarely longer, 2-7 mm. wide : panicle 2-4 cm. long, broadly ovate : spike- 
lets elliptic, about 1.3 mm. long and 0.7 mm. wide, pubescent with short spreading hairs. 

In low pine lands, peninsular Florida. Spring and summer. 

74. Panicum tilfolium Nash. A nearly glabrous tufted perennial. Stems slender, 
2-4 dm. tall, finally a little branched : leaves 3, rarely 4, the uppermost one much above 
the middle of the stem and generally but a little below the panicle ; sheaths often but ] 
as long as the internodes ; blades erect or nearly so, firm, lanceolate, the margins thick- 
ened and cartilaginous, 1.5-6 cm. long, 1.5-5 mm. wide : panicle 2.5-6 cm. long, broadly 
ovoid, its branches ascending : spikelets 1.5 mm. long and about 0.7 mm. wide, ellipsoid, 
densely pubescent with short spreading hairs. 

In sandy soil, North Carolina to northern Florida and Mississippi. Spring and summer. 

75. Panicum glabrissimum Ashe. Stems tufted, rather slender, 3-4 dm. tall, finally 
somewhat branched : leaves about 3, distant ; sheaths less than 2 as long as the internodes ; 
blades erect or ascending, pubescent on the lower surface with short hairs, 1.5-3 5 cm. 
long, 2-3 mm. wide : panicle long-exserted, 3-5 cm. long, ovate, its branches ascending : 
spikelets 1.5 mm. long and a little less than 1 mm. wide, oval, pubescent with spreading 
hairs. 

In dry soil, North Carolina. Summer. 

76. Panicum longiliguliituin Xash. A tufted nearly glabrous perennial. Stems 4-5 
dm. tall, slender, finally branched, the branches fasciculately much divided and forming 



dense masses at their ends : leaves 4 or 5 ; sheaths minutely pubescent between the prominent 
nerves ; ligule of erect silky hairs about 3 mm. long ; blades ascending, lanceolate, ob- 



scurely and minutely pubescent on the lower surface, the primary ones 2.5-3 cm. long, 
about 3 mm. wide : panicle 5-6 cm. long, oval, its branches spreading : spikelets about 1.3 
mm. long and 0.8 mm. wide, oval, densely pubescent with spreading hairs. 

In dry sandy soil, western Florida. Summer. 

77. Panicum paucipiliun Nash. A tufted nearly glabrous perennial. Stems 6-10 
dm. tall, finally somewhat branched : leaves 5-8 ; sheaths with the exterior margin ciliate 
toAvard the summit ; blades erect or ascending, thickish, rather firm, sometimes minutely 
puberulent on the lower surface, usually with a few hair-bearing papillae at the base, the 
lower and larger primary ones 6-9 cm. long, 5-7 mm. wide : panicle 5-10 cm. long, rather 
dense, its branches erect-ascending or erect: spikelets numerous, about 1.4 mm. long and 
0.8 mm. wide, oval, pubescent with spreading hairs, the first scale about J as long as the 
spikelet. 

In wet soil, soutliern Xew Jersey to Florida and Mississippi. Summer. 

78. Panicum octonodum J, G. Smith. Glabrous. Stems erect, 7-11 dm. tall, finally 
branched : leaves 6-8 ; sheaths much shorter than the internodes ; blades erect, firm, 4-11 
cm. long, 4-8 ram. wide, lanceolate : panicle 9-13 cm. long, oblong, dense, 2-4 cm. wide, 
its branches erect or erect-ascending: spikelets 1.3 mm. long and about 0.8 mm. wide, 
oval, glabrous. 

In wet places, Xew Jersey to Alabama and Texas. Spring and summer. 



\ 



POACEAE 



99 



I 



79. Panicum leucothrix Nash, A villous densely tufted perennial. Stems 3-6 
dm. tall, erect, finally much branched : jirimary leaves 3-5 ; sheaths usually less than ^ as 
long as the internodes, the pubescence ascending ; blades erect, rather firm, lanceolate, 
densely and softly pubescent on the lower surface with short spreading hairs, glabrous 
above, 3-5 cm. long, 4-6 mm. wide: primary panicle usually 3-5 cm, long, rarely larger 
or smaller, broadly ovate, its branches ascending : spikelets about 1.2 mm. long and about 
0.6 mm. wide, oval, pubescent with short spreading hairs. 

In usually dry sandy soil, southern New Jersey to Florida and Texas. Spring and suminer, 

80. Panicum parvispiculum Xash. A much tufted perennial. Stems glabrous, or 
more or less appressed-pubescent below, erect, finally branched : leaves 4 or 5 ; sheaths 
shorter than the internodes, glabrous, or the lower ones more or less pubescent ; blades 
erect or ascending, firm, lanceolate, acuminate, the primary ones 3-10 cm. long, 2-7 mm. 
wide, minutely but densely pubescent on the lower surface : panicle 6-10 cm. long, broadly 
ovate, its branches ascending: spikelets 1.3 mm. long and about 0.8mm. wide, oval, 
densely pubescent with spreading hairs. 

In dry soil, North Carolina to Florida and Mississippi. Spring and summer. 

81. Panicum uitldum Lam. Stems tufted, 4-8 dm. tall, glabrous, finally much 
branched : leaves 4 or 5 ; sheaths glabrous, ciliate on the margin with long hairs ; blades 
erect, glabrous, or the lower surface sometimes minutely pubescent with short hairs, ciliate 
at the base, the primary ones 2-8 cm. long, 3-8 mm. wide, lanceolate, firm, the blades on 
the branches much smaller : panicle 3-8 cm. long, broadly ovoid, its branches ascending : 
spikelets about 1.5 mm. long and 0.8 mm. wide, obovoid, densely pubescent with short 
spreading hairs. 

In dry soil, New York to Georgia. Summer. 

82. Panicum Tenuesse^nse Ashe. Stems tufted, 4-6 dm. tall, rather weak and as- 
cending, papillose-hirsute with long spreading hairs, finally much branched and prostrate 
and forming broad mats : leaves 4 or 5 ; sheaths densely papillose-hirsute with long 
spreading hairs ; blades ascending, lanceolate, the lower surface densely and softly pubes- 
cent with short hairs, the upper surface with scattered hairs and those at the base ven' 
long, the primary blades 4-10 cm. long, 5-10 mm. wide, those on the branches much 
shorter and spreading with the upper surface nearly glabrous: panicle 7-10 cm. long, 
ovoid, its branches ascending : spikelets 1.7-2 mm. long, 0.8-0.9 mm. wide, elliptic or 
obovoid, strongly pubescent with long spreading hairs. [P. Wihningtonense Ashe.] 

In woods, New York and Illinois to Tennessee and Florida. Summer and fall. 

83. Panicum ciliosum Nash. Stems tufted, 3-5 dm. tall, papillose-hirsute with 



spreading hairs, finally much branched : leaves 4 or 5 ; sheaths densely hirsute with 
spreading hairs, hirsute on the margins ; blades erect or ascending, narrowed toward the 
base, ciliate on the margins, glabrous above, the lower surface densely pubescent between 
the nerves with short spreading hairs : panicle about 8 cm. long, broadly ovoid, its axis 
pubescent with short hairs, the branches spreading : spikelets a trifle less than 2 ram. long 
and about 0.9 mm. wide, elliptic, strongly pubescent with rather long spreading hairs. 

In dry soil, Mississippi. Summer and fall. 

84. Panicum lanuginosum EIL Stems and leaves villous with spreading hairs, those 
on the blades and upper part of the stems shorter. Stems leafy, tufted, 3-8 dm. tall, erect, 
finally branched, a smooth ring below each barbed node : leaf-blades erect, lanceolate, 4-13 
cm. long, 4-9 mm. wide : panicle ovoid, 4-10 cm. long, the axis pubescent, the branches 
ascending: spikelets numerous, broadly obovoid, about J. 5 mm. long and 0.8 mm. wide, 
densely pubescent with spreading hairs. 

In dry sandy soil, southern New Jersey to Florida and Alabama. Summer. 

85. Panicum ThurowU Scribn. & Smith. Stems tufted, 4-G dm. tall, at fii>it erect 



and simple, finally branched, papillose-hirsute below with long hairs, the pubescence above 
softer : leaves 4 or 5 ; sheaths densely papillose-hirsute witli long spreading hairs ; blades 
erect or ascending, densely long-villous on the lower surface, the upper surface pubescent 
with long stiflf* spreading hairs, or sometimes nearly glabrous : panicle 6-9 cm. long, 
broadly ovoid, its branches ascending: spikelets about 1.8 mm. long and 0.8 mm. wide, 
elliptic, pubescent with spreading hairs. 



In dry soil, Texas. Summer. 



86. Panioum filiculme Ashe, Stems densely tufted, slender, finally much branched, 
2-3 dm. tall, minutely pubescent above : leaf -sheaths strongly hirsute with very long hairs ; 
blades erect, the primary ones 1.5-3 cm. long, 2-4 mm. wide, papillose-pubescent on both 
surfaces, or sometimes glabrous beneath, the hairs on the upper surface exceedingly long 
and r^opious: primary panicle long-cxserted, 2-3 cm. long: spikelets broadly obovoid t.» 



100 



POACEAE 



elliptic, 1.5 luiu. long, pubescent. [P. Albemarlense Ashe. P. microphyllum Ashe. P. 
subvillosum Ashe.] 

In dry soil, New Jersey to Georgia. Summer. 

87. Panicum unciphyllum Trin. Stems at first erect and simple, later profusely 
branched and leaning or ascending, glabrous or pubescent : leaf-sheaths hirsute, often 
papillose ; blades hirsute, especially beneath, erect or spreading, those on the main stem 
5-8 cm. long, those on the branches much shorter : primary panicle less than 8 cm. long, 
ovoid, its branches ascending, the lateral panicles much smaller : spikelets hardly 2 mm. 
long, pubescent. [P. pubescens A. Grny, not. Lam.] 

In dry soil, common, Maine and Quebec to British Columbia, Georgia, the Indian Territory and 
Arizona. Summer. 

88. Panictun Lindheimeri Nash. A nearly glabrous perennial. Stems 3-5 dm. 
tall, finally much branched : primary leaves 6-7 ; sheaths shorter than the internodes, 
ciliate on the margin, usually sparingly tuberculate-hirsute ; blades ascending, lanceolate, 
acute, smooth on both surfaces, usually 2-7 cm, long, sometimes longer, 4-10 mm. wide : 
primary panicle 3-5 cm. long, broadly ovate or oval, its branches spreading : spikelets about 
1.5 mm. long and about 0.8 mm. wide, broadly obovoid, pubescent with spreading hairs. 

In dry soil, Georgia to Texas and the Indian Territory. Spring and summer. 

89. Panicum sphaerocArpon Ell. Stems generally erect, simple or somewhat 
branched at the base, 2.5-6 dm. tall, glabrous : leaf -sheaths usually shorter than the inter- 
nodes, glabrous, the margins ciliate; blades 5-10 cm. long, 4-14 mm. wide, rough above, 
smooth beneath, the margins cartilaginous and minutely serrulate, ciliate toward the base: 
panicle ovoid, 5-10 cm. long : spikelets less than 2 mm. long, nearly spherical, or a little 
longer than thick, obtuse. 

In dry soil, southern Ontario, New York and Missouri to Florida, Texas and Mexico. Summer and 
fall. 

90- Panicum inflktum Scribn. & Smith. Stems 3-4 dm. tall, branched, finally pros- 
trate and rooting at the lower nodes : sheaths compressed, inflated, very loosely embracing 
the stem, strongly striate, marked with white tubercles, ciliate on the margin ; blades as- 
cending, lanceolate, ciliate at the base, 3-7 cm. long, 7-10 mm. wide, 'flat, acuminate into an 
obtuse point : panicle much exserted, 6-8 cm. long, oval, its branches ascending : spikelets 
oval, 1.3 mm. long and about 0.9 mm. wide, minutely and sparsely pubescent, [P. Mmissip- 
piense Ashe.] 

In sandy soil, Mississippi. Fall. 

91. Panicum erectif olium Nash. A nearly glabrous tufted perennial. Stems erect, 
5-7 dm. tall, finally sparingly branched, the branches erect : primary leaves usually 5-7 ; 
sheaths usually about h as long as the internodes, ciliate on the margins ; blades erect, 
firm, ciliate on the margins toward the base, lanceolate, acuminate, 5-10 cm. long, 5-13 
mm. wide : panicle elliptic, 8-12 cm. long, its branches erect-ascending : spikelets numer- 
ous, 1-1.3 mm. long and 0.6-0.8 mm. wide, elliptic to oval, pubescent witli spreading 
hairs. [P. Floridanum Chapm.] 

In wet soil or swamps, Florida to Mississippi. Spring and summer. 

92. Panicum polyAnthes Schult. Stems generally erect, 6-9 dm. tall, simple, gla- 
brous : leaf-sheaths glabrous, longer than the internodes; blades 1-2 dm. long, 1-2.5 
cm. wude, long-acuminate, smooth, cordate-clasping and sparingly ciliate at the base : 

f)anicle 7-20 cm. long, ovoid to oblong, its branches slender, ascending : spikelets 1.5 mm. 
ong, obovoid to nearly spherical, numerous, puberulent* [P. mierocarpon Muhl.] 

In woods and along thickets, southern New York and Pennsylvania to Michigan, Florida, Louis- 
iana, Nebraska and Texas. Summer and fall. 

93. Panicum cbrysopsidifolium Xash. Stems tufted, 2.5-5 dm. tall, stout, finally 
branched, strongly pubescent below with long stiff nearly appressed hairs, the upper ;por- 
tion sparingly pubescent : leaves 5 or 6 ; sheaths papillose-hirsute with ascending hairs ; 
blades lanceolate, acuminate, 3-12 cm. long, 3-10 mm. wide, thick, firm, rather sparingly 
papillose-hirsute on both surfaces with long spreading stiff hairs : panicle 5-7 cm. long, 
broadly ovoid, its branches spreading: spikelets about 2 mm. long and 1.2 mm. wide, 
broadly obovoid, coarsely and strongly nerved, pubescent with short spreading hairs. 

In dry sandy soil, middle Florida. Spring. 

94. Panicum pseudopub6scens Nash. A densely tufted pubescent perennial. Stems 
2-4 dm. tall, hirsute with ascending hairs, finally branched, the nodes barbed : leaves 



usually 3 ; sheaths densely hirsute with spreading luiirs ; blades erect, rather firm, lanceo- 




wide, obovoid, densely pubescent with spreading hairs. 

In sandy soil, Alabama. Spring and summer. 



POACEAE 



101 



95. Panicum Atlanticum Nash. Densely papillose-liirsute, the hairs on tlie sheaths 
and upper surface of the leaf-hlades exceedingly long. Steins tufted, erect, often from an 
ascending base, 3-5 dm. tall, finally branched, the nodes barbed with spreading hairs : 
sheatlis shorter tlian the internodes ; blades erect, lanceolate, rather firm, the primary ones 
usually 6-8 cm. long, rarely longer or shorter, 4-8 ram. wide : panicle 5-7 cm. long, 
broadly dvoid, its branches ascending : spikelets barely exceeding 2 nmi. long and about 1.2 
mm. wide, broadly obovoid, pubescent with spreading hairs. 

In dry soil, southeastern New York to Georgia and Mississippi. Summer. 

96. Panicum villosissimum Niush. Whole plant densely pubescent with long 
spreading hairs. Stems 3-6 dm. tall, erect or ascending, the nodes barbed : leaf-blades 
linear-lanceolate, 5-10 era. long, 4-9 mm. wide, erect, yellowish green : panicle long- 
exserted, broadly oyate, 6-10 cm. long, its branches spreading or ascending, sometimes 
flexuous, the lower ones 3-6 cm. long: spikelets elliptic, 2.5 mm. long and about 1.25 
mm. wide, obtuse or acutish, pubescent. 

In alluvial soil, Georgia. Spring and summer. 

97. Panicum xanthosp6nnuin Scribn. & Molir. Stems tufted, 1-2 dm. tall, hii-sute, 
finally branched : leaf-sheaths hirsute ; blades 3-6 cm. long, 5-8 mm. wide, lanceolate, 
pubescent on both surfaces with long rather stiff spreading hairs, those on the upper surface 
the longer: panicle 3-4 cm. long, its branches ascending: spikelets yellowish, about 2.3 
mm. long and 1 mm. wide, elliptic, pubescent with long weak haii-s. 

In dry sandy soil, Alabama. Spring and fall. 

98. Panicum Commonsianiini Ashe. Stems tufted, 3-5 dm. tall, finally branched, 
pubescent beloAV with long nearly appressed hairs, the upper portion glabrous or 
puberulent, the nodes bearded with spreading hairs : primary leaves usually 2 or 3 ; sheaths, 
at least the lower ones, pubescent with nearly appressed hairs ; blades erect, lanceolate, 
strigose on the lower surface, the upper surface glabrous or with some long spreading hairs 
toward the base, the primary ones 4-8 cm. long, 3-6 mm. wide : panicle 4-8 cm. long, 
ovate, its branches spreading or ascending : spikelets 2.5 mm. long and about 1.3 mm. 
wide, obovoid, pubescent with spreading hairs, the first scale about I as long as the spikelet. 

In dry Bandy soil near the coast, New Jersey and Delaware. Spring and summer. 

99. Panicum strictifolium Nash. Stems tufted, 2.5-5 dm. tall, strongly pubescent 
toward the base with long soft hairs, puberulent toward the summit, finally nmch branched : 
leaves 3 or 4 ; sheatlis much shorter than the internodes, the lower ones densely pubescent 
with long soft appressed hairs ; blades erect or nearly so, rather firm, narrowly lanceolate, 
the upper surface often with a few long scattered hairs, the primary blades 4-7 cm. lon^, 
3-5 mm. wide : panicle 5-7 cm. long, broadly ovoid, its axis and spreading branches mi- 



nutely pubescent : spikelets obovoid, 3 mm, long and about 1.5 mm. wide, densely pubes- 
cent with rather long spreading hairs. 

In dry sandy soil, peninsular Florida. Spring and summer. 

100. Panicum ciliiferum Nash. Stems tufted, 2-5 dm. tall, finally much branched, 
densely hirsute below with long nearly erect hairs, spai-sely pubescent above : primary 
leaves usually 3, sometimes 2; sheaths densely hirsute with hmg ascending hairs ; blades 



erect or ascending, lanceolate, the upper surface glabrous or sometimes with some long 
erect hairs near the base, the lower surface strongly strigose, ciliate with long hairs, the 
primary ones 3-8 cm. long, 4-10 mm. wide: primary panicle ample, 6-11 cm. long, 
broadly oval, its branches spreading or ascending : spikelets about 2.75 mm. long and 1-1.2 
mm. wide, elliptic, pubescent with long spreading hairs. 

In dry sandy soil, peninsular Florida. Spring and summer. 

101. Panicum epilifolium Nash. A glabrous tufted perennial. Stems 2-3.5 dm. 
tall : leaves 2 or 3 ; slieaths minutely pubescent at the apex, ciliate on both margins with 
long slender hairs ; blades widely spreading, linear-lanceolate, 4-7 cm. long, 5-7 mm. 
Tvide, minutely pubescent on the upper surface between the nerves : panicle 5-7 cm. long, 
ovate, its branches spreading or ascending : spikelets 3 mm. long and about 1.5 njm. wide, 
oval, obtusely apiculate, densely pubescent with short spreading hairs, the first scale about 
i as long as the spikelet. 

In dry sandy soil, peninsular Florida. Spring. 

102. Panicum pedicell^tum Vasey. A pubescent pere*nnial. Stems 3-4 dm. tall, 
pubescent with short ascending hairs, finally branched : leaves 4 or 5 ; sheaths shorter 
than the internodes, pubescent between the nerves with short hairs, ciliate on the margins 



with long hairs ; blades erect or nearly so, linear-lanceolate, puljescent on both surfaces 
with rather short spreading hairs, usually ciliate at or toward the base, the primary ones 
4-9 cm. long, 2.5-4 mm. wide, those on the branches smaller : panicle 3-4 cm. long, nar- 
row, its branches erect-ascending : spikelets 4 mm. long and 1.5 mm. wide, the scales 



102 



POACEAK 



rather distantly inserted on the rachilla, the first scale about 2 as long as the spikelet, the 
second and third scales densely pubescent with short spreading hairs. 

In dry ground, Texas. Spring and summer. 

103. Panicum mdlacon Nash. A densely tufted usually purplish perennial, with 
the stem and sheaths strongly hirsute with ascending or nearly erect hairs. Stems,3-5 dm. 
tall, finally much branched : sheaths shorter than the internodes ; blades erect, acuminate, 
softly pubescent on both surfaces with short hairs : panicle 7-10 cm. long, oval, its branches 
ascending : spikelets 3.5 mm. long and about 1.5 mm. broad, obovoid, densely pubescent 
with rather long spreading hairs, the first scale fully i as long as the spikelet and 6-nerved. 

In dry sandy soil, peninsular Florida. Spring. 

104. Panicum H^Ueri Nash. Stems tufted, 2-4 dm. tall, finally branched, appressed- 
pubescent below w^ith long hairs, the nodes sparingly barbed : leaves 5 ; sheaths ciliate on 
the exterior margin, bearing between the prominent nerves scattered papillae from which 
sometimes arise stiff hairs, the internerves of all but the upper sheaths minutely pubescent ; 
blades broadly lanceolate, thin, sparsely ciliate at the rounded base, the primary ones 6-8 
cm. long, 6-12 mm. wide : panicle usually included at the base, 6-8 cm. long, its branches 
ascending: spikelets 3.25-3.5 mm. long and about 1.5 mm. wide, ellipsoid or somewhat 
obovoid, pubescent toward the base with a few scattered hairs. 

On stony wooded hillsides, southern Texas. Spring. 

105. Panicxim scabriiisculTiin Ell. Stems glabrous or pubescent, 8-14 dm. long, 
erect, sometimes rooting at the lower nodes, finally branched : leaves 6-8 ; sheaths glabrous 

, or pubescent; blades erect or ascending, linear-lanceolate, glabrous, 1-2 dm. long, 8-12 
mm. wide : panicle 1-2 dm. long, broadly ovoid, its branches spreading or ascending : 
spikelets lanceolate, glabrous, 2-2.3 mm. long and 1 mm. broad, ovate to ovate-lanceolate, 
acute, the nerves of the flowering scale very prominent. 

In swampy places and ponds, Virginia to Florida and Texas. Spring and summer. 

106. Panicum scoparium Lam. Stems erect, 6-12 dm. tall, simple, finally much 
branched above, villous : leaf -sheaths villous ; blades softly pubescent, those on the main 
stem 10-18 cm, long, 10-16 mm. wide, distant, those on the branches 2.5-6.5 cm. long, 4—10 
mm. wide, crowded : primary panicle 7-15 cm. long, ovoid, its branches ascending, the 
secondary panicles much smaller : spikelets ovoid to oval, about 2.5 nun. long, pubescent. 
[P. viscidum EIL] 

In moist soil, New Jersey to Indiana, the Indian Territory, Florida and Texas. Summer. 

107. Panicum equilaterale Scribn. A tufted nearly glabrous perennial. Stems 
4-8 dm. tall, finally branched, the branchlets crowded at the end of the branches : primary 
leaves 4 or 5 ; sheaths ciliate on the margins, shorter than the internodes : primary blades 
spreading, elongated, linear to linear-lanceolate, 8-18 cm. long, 7-15 mm. wide, those on 
the branches much smaller but similar in sliape : primary panicle 7-9 cm. long, broadly 
ovate, its branches somewhat ascending : spikelets about 3.5 mm. long and about 1.3 mm. 
wide, elliptic, somewhat acute, pubescent with short spreading hairs. 

In dry soil, peninsular Florida. Summer. 

108. Panicum Ashei G. Pearson. Stems tufted, 2-4 dm. tall, erect, usually spar- 
ingly branched, rarely much branched and prostrate, puberulent : leaves 3 or 4 ; sheaths 
usually less than J as long as the internodes, ciliate on the overlapping margin ; 
blades usually erect or ascending, sometimes spreading, lanceolate, sparsely ciliate at the 
base with long hairs, usually 5-8 cm. long, rarely longer, 6-10 mm. wide, occasionally 
broader, a little cordate at the base, the upper blades about the same length, the lower ones 
shorter, the early basal blades ciliate : panicle 5-7 cm. long, its branches ascending : spike- 
lets about 2.3 mm. long and about 1 mm. wide, elliptic, pubescent with ratlier long ascend- 
ing hairs. 

In dry woods, southern Connecticut and New York to Tennessee and Georgia ; also in Missouri 
Summer. 

109. Panicum ovale EIL Stems tufted, 3-7 dm. tall, villous, finally somewhat 
branched, the branches divergent : primary leaves usually 3-5 ; sheaths shorter than the 
internodes, softly pubescent, ciliate on the margin ; upper blades ovate-lanceolate, crowded 
and clasping at the base, pubescent on both surfaces, ciliate on the margins, the primary 



s 5-10 cm. long, 1-2.5 cm. wide: primary panicle 7-12 cm. long, oval, its branches as- 
cending : spikelets 2.5-3 mm. long and about 1 mm. wide, rarely larger, pubescent with 
spreading hairs. [P. commeMnaefolium Ashe. P. Cwrram Ashe,] 

In dry soil, Xortli Carolina to Florida and Louisiana. Spring and summer. 

110. Panicum Manat6nse Nash. Stems 2-4 dm. long, finally decumbent and much 
branched : leaf-sheaths ciliate on the margin ; blades erect or nearly so, lanceolate, 3-9 



POACEAE 



103 



. long, 7-15 nun. wide, sparsely ciliate at the base : panicle 4-6 cm. long, its branches 
ascending: spikelets elliptic, about 3 mm. long and 1,3 mm. wide, very acute, strongly 
pubescent with spreading hairs. 

In hammock land, southern peninsular Florida. Summer. 

111. Panicum commutatuni R. & S. Stems tufted, glabrous, erect, 3-fi dm. tall^ 
finally rather sparingly branched : leaves 3 or 4 ; sheaths glabrous, ciliate on the margin ; 
blades ciliate on the margin, otherwise glabrous, cordate and clasping at the base, those on 
the stem larger than the basal ones, 5-12 cm. long, 1-2 cm. wide, ovate-lanceolate : panicle 
5-10 cm. long, broadly ovoid, its branches spreading or ascending: spikelets 2.5-3 mm. 
long and about 1 mm. wide, elliptic, obtuse or acutish, pubescent. 

In dry places, New York to Tennessee, Missouri, Florida and Texas. Summer. 

112. Panicum mutdbile Scribn. & Smith. Stems 4-8 dm. tall, tufted, glabrous, at 
first erect, finally prostrate and much branched : leaves 3 or 4 ; sheaths glabrous, excepting 
the ciliate margin ; blades glabrous, cordate and clasping at the base, ovate-lanceolate, tlie 
basal ones larger than those on the stem and conspicuously ciliate with hmg hairs, tlie 
stem-leaves with blades 6-12 cm. long and usually 1-2 cm. wide : panicle 1-1.5 dm, long, 
broadly ovoid, its branches ascending : spikelets about 3 mm. long and 1-1.2 mm. wjde, 
pubescent. 

In sandy soil, North Carolina to Florida and Mississippi. Summer and fall. 

113. Panicum Jodrli Vasey. Stems tufted, glabrous, at first erect, finally prostrate 
and mucli branched : leaves 3 or 4 ; sheaths glabrous, excepting the ciliate margin ; blades 
ovate-lanceolate, cordate and clasping at the base, glabrous, those on the stem, which are 
smaller than the basal ones, 5-10 cm. long, 1-2 cm. wide : panicle 6-10 cm. long, ovoid, 
its branches ascending : spikelets 2.5-3 mm. long and 1-1.2 mm, wide, obtuse or sometimes 
acutish, pubescent. 

In sandy soil, Florida to Louisiana. Spring to fall. 

114. Panicum clandestinum L. Stems tufted, 6-14 dm. tall, glabrous, or some- 
times papillose-hirsute below, finally much branched, the branches clothed with the densely 
papillose-hispid overlapping leaf-sheaths : primary leaves usually 5-7, their sheaths shorter 
than the internodes, ciliate on the exterior margin, at least the lower ones strongly papillose- 
hispid with spreading hairs ; blades spreading or ascending, glabrous on both surfaces, 
ciliate at the cordate and clasping base, the primary ones 1-2 dm. long, 1.5-2.5 cm. wide, 
acuminate, lanceolate, those on the branches ovate-lanceolate and usually less than 1 dm, 
long: primary panicle long-exserted, 9-12 cm. long, rarely larger, broadly ovate, its 
branches ascending, the later panicles wholly or partially concealed in the sheaths : spike- 
lets 2.7-3 mm. long and about 1.3 mm. wide, elliptic, pubescent with spreading hairs. 

In moist or wet places, Rhode Island and southern New York to Florida. Summer and fall. 

115. Panicum malacophyllum Nash. A perennial with the stems and sheaths 
papillose-hirsute with long spreading hairs and the nodes barbed. Stems 3-4 dm. tall, finally 
somewhat branched above : leaves 4 or 5 ; sheaths about 2 ^^ long as the internodes ; blades 
ascending, lanceolate, softly pubescent on both surfaces, 5-7 cm. long, 5--7 mm. wide : 
panicle 4-5 cm. long, its axis and spreading branches densely hirsute with spreading hairs : 
spikelets 3 mm. long and about 1.5 mm. Avide, broadly oval or obovoid, densely hirsute with 
long spreading hairs. 

In dry soil, Tennessee and the Indian Territory. Spring. 

116. Paalcum pemervosum Nash. A glabrous perennial. Stems 3-5 dm. tall, 
finally branched : leaves 3 or 4 ; sheaths ciliate on the exterior margin ; blades erect or 
ascending, narrowed toward the base, the larger ones 5-10 cm. long, 5-9 mm. wide, ciliate 
toward the base with a few long hairs, the lower ones usually pul)escent on the lower sur- 
face, ciliate for f their length : panicle 7-12 cm. long, its branches ascending : spikelets 3 
mm. long and 1.8 mm. wide, broadly oval, turgid, glabrous. 

In woods, eastern Texas. Spring. 

, 117. Panicum ollgosdnthes Schult. Stems tufted, erect, 3-8 dm. tall, villous, 
finally fasciculatelv branched : leaves 4 or 5 ; sheaths, at least the lower ones and those on 
the branches, papillose-hispid, ciliate on the margin ; blades erect or ascending, 5-10 cm. 
long, 5-10 mm. wide, lanceolate, softly and densely pubescent on the lower surface, the 
upper surface glabrous, or with a few long hairs at the base : primary panicle 6-8 cm. long, 
its branches ascending : spikelets about 3.5 mm. long and 1.7 mm. broad, oval, pubescent. 
[P. pauclflorum Ell., not R. Br.] 

In dry soil, Virginia to Georgia and Mississippi. Summer and fall. 

118. Panicum Scribnerianum Nash. Stems tufted, erect, 1.5-6 dm. tall, simple, 
finally dichotomously branched above, sparingly pubescent or glabrous: leaf-sheaths 
stronglv papillose-hispid ; blades 5-10 cm. long, 6-12 mm. wide, spreading, glabrous : 



lO-t 



POACEAE 



primary panicle ovoid, 4-8 cm. long", its branches spreading: spikelets turgid, obovoid, 
about 3 mm. long, glabrous, or sometimes pubescent with short spreading hairs. 

In dry soil, Vermont, Massachusetts and Xew Jersey to Minnesota, British Columbia, Missouri, the 
Indian Territorj' and Arizona. Sjiring and summer. 

119. Panicuin Raven§lii Scribn. & Mer. Stems tufted, erect, 4-6 dm. tall, finally 
branched, papillose-hirsute below with ascending hairs, the pubescence above softer : 
leaves 3 or 4 ; sheaths densely papillose-hii'sute with ascending luiirs ; blades erect or 
ascending, glabrous above, densely and softly pubescent below, broadly lanceolate, 8-12 
cm. long, 1-2 cm. wide, cordate at the clasping base : panicle 8-10 cm. long, its branches 
ascending : spikelets about 4 mm. long and 1.8 mm. wide, obovoid, pubescent with rather 
weak hairs. [P. scoparmm Ell., not Lam.] 

In woods. District of Columbia to Florida and Louisiana. Summer and fall. 

120. Panicuin macrocarpon Le Conte. Stems 3-9 dm. tall, erect, simple, or some- 
■what branclied above, the nodes, at least the upper ones, naked : leaf-slieaths glabrous, 
cilinte ; blades 7-18 cm. long, 2-4 cm. wide, cordate-clasping at the base, acuminate, 
glabrous on both surfaces, ciliate : panicle 8-15 cm, long, usually long-exserted, rarely in- 
cluded, its branches more or less ascending : spikelets 3-4 mm. long, turgid, oval to obo- 
void, pubescent. 

In woods or on dry hillsides, Xew Hampshire to North Carolina, Iowa and Kansas. Summer, 

121. Panicum Porteri^nuin Xash. Stems tufted, erect, the upper part, including 
the panicle axis, and sometimes also the lower portion, pubescent with short hairs, or 
sometimes glabrous, finally branching, the nodes densely barbed with long spreading hairs : 



leaves 4-6 ; sheaths ciliate on the margin, otherwise glabrous, or sometimes the lower ones 
8oftly pubescent ; blades ovate-lanceolate, cordate and clasping at the base, paler on the 
lower surface, glabrous, or the upper surface sometimes sparsely pubescent, 6-12 cm. long, 
the larger ones 2-4 cm. wide : panicle 6-12 cm. long, its branches ascending : spikelets 
4-6 mm. long, 1.5-2 mm. wide, the scales distant, pubescent with long weak hairs. [P. 
latifolium Chapm., in part, not L.] 

In rocky woods, Xew York to Florida and Texas. Summer. 




, Panicum pubif olium Nash. A softly pubescent densely tufted perennial. Stems 
3-7 dm. tall, pubescent with soft weak spreading hairs, finally branched, the nodes densely 
barbed with long hairs : leaves 3-5 ; sheaths ciliilte on the margins, densely pubescent, at 
least all but the uppermost, with spreading weak usually long hairs ; blades spreading or 
ascending, ovate-lanceolate to ovate, acuminate, gradually narrowed to the rounded cordate- 
clasping base, pubescent on both surfaces with short spreading hairs, the upper primary 
blades 7-11 cm. long and 2-3 cm. broad, the lower smaller : primary panicle usually but 
little exserted, sometimes included at the base, 7-11 cm. long, its axis, as Avell as the 
branches, densely pubescent with short soft spreading hairs, the branches spreading or 
ascending : spikelets 4-5 mm. long and about 1.6 mm. broad, narrowly obovoid, the scales 
distant, strongly pubescent with long spreading hairs. [P. latifolium Chapm., in part, not L. ] 

In rocky woods, Xew York to Missouri, Florida and Mississippi. Summer and fall. 

123. Panicum latifolium L. An intricately much branched shrub, sometimes 2-3 
nu tall. Leaves crowded and numerous ; sheaths overlapping, ciliate on the margin ; 
blades spreading or ascending, glabrous, acuminate, the larger ones 8-10 cm. long, 13-35 
mm. wide, those on the ultimate divisions considerably smaller : panicle 1 dm. long or 
less, its branches spreading or ascending : spikelets turgid, 4-5 mm. long, the scales tipped 
with woolly hairs, the first scale very broad, clasping the base of the spikelet. [P, divari- 
catum L.] 

In dry soil, southern peninsular Plorida. Spring to fall, Sjiall Cank. 

32. PHANOPYRUM Nash. 
Tail grasses with long flat linear or lanceolate leaf-blades which are cordate and clasp- 



in«: at the base, and ample panicles with the spikelets arranged in pairs or in short branchlets 
on one side of its branches. Spikelets on rather short pedicels, acuminate ; scales 4, 
acuminate, strongly nerved, the first scale % as long as the spikelet or more, a little shorter 
than or equalling the third, the second scale considerably exceeding the third, the fourth 
scale less than i- as long as the spikelet, chartaceous, indurated in fruit. Stamens 3. 
Styles long and slender, free to the base. Stigmas plumose. 

1. Phanopyrum gymnocarpon (Ell.) Nash. A glabrous perennial. Stems leafy, 
6-12 dm. tall : leaf-blades 4 dm. long or less, 1-4 cm. wide : panicle 1-2 dm. long, its 
bmnches long and ascending : s})ikelets o-d mm. long. [^Panicum gymnocarpon Ell.] 

In moist places, Georj^ia and Florida to Texas. Summer and fall. 



4 



POACEAE 



105 



h 
\ 



33. SACCIOLEPIS Nash. 



Perennials with flat leaf-blades and contracted dense panicles. Spikelets nunierons. 
Scales 4, the 3 outer membranous ; 2 outer scales empty, the first scale small and narrow, 



the second one large and broad, 11-nerved, saccate and gibbous at the base, the third scale 
enclosing a palet and staminate flower, the fourth scale chartaeeous, finally indurated, about 
2 as long as the second scale, enclosing a palet of similar texture and a perfect flower. 
Stamens 3. Styles distinct. Stigmas plumose. 

+ 

1. Sacciolepis gibba (Ell.) Nash. Stems erect or ascending, usually rooting at the 
lower nodes, finally dicliotoniously branched, 3-20 dm. long: leaf-sheaths papillose-hirsute, 
at least the lower ones ; blades lanceolate, spreading or ascending, long-acuminate, some- 
times hirsute on one or both surfaces, 4-20 cm. long, 4-22 mm. wide : panicle contracted, 
6-30 cm. long, 1.5-2 cm. wide : spikelets 4-5 mm. long, ovate-lanceolate. \_Panicum 
gihbum Ell.] 

In swamps and low grounds, Virginia to Tennessee, Missouri, Florida and Louisiana, cliietly 
along the coast. Also in Cuba. Summer and fall. 

34. STEINCHISMA Raf. 

Perennial tufted grasses, with erect stems, flat leaf-blades and loose open panicles. 
Spikelets l-flowered, the 3 outer scales membranous, the third scale bearing in its axil a 
much enlarged and inflated papery palet which exceeds in length the fourth scale ; first 
scale short, the second one about as long as the spikelet ; fourth scale indurated in fruit 
and enclosing a palet of similar texture and a perfect flower. Styles long, united only at 
tlie base. Stigmas plumose. 

1. Steinchisma hians (Ell. ) Nash. Glabrous. Stems erect, 3-8 dm. tall, sometimes 
creeping at the base : leaf-blades 7-13 cm. long, 2-6 mm. Avide, acuminate, usually erect : 
panicle 7-20 cm. long, its branches few, generally spreading : spikelets about 2 mm, long. 
[Panicum hians Ell.] 

In moist ground, North Carolina to Missouri, Florida and Texas. Summer and fall. 

35. CHAETOCHLOA Scribn. 

Annual or perennial grasses, with usually flat, sometimes complanate, leaf-blades and 
dense terminal cylindric spike-like or narrowly thyrsoid panicles. Spikelets with one or 
a cluster of 2-several sterile barbed bristle-like persistent branches. Scales 4, the 3 outer 
membranous, the first often very short and together with the larger second one empty, the 
third scale frequently longer than the second, empty, or rarely enclosing a j^alet and also 
sometimes a staminate flower, the fourth scale usually shorter than the spikelet, charta- 
eeous, glabrous, shining, often transversely rugose, finally indurated, obtuse, enclosing 
a shorter palet of similar texture and a perfect flower. Stamens 3. Styles distinct, 
elongated. Stigmas plumose. \_Seiaria Beauv., not Achar.] Foxtail. Foxtail Gbass. 

Inflorescence with the spikelets racemosely arranged : bristles 5-16 at the base of 
each spikelet, invofucrate. 
Annual ; bristles tawny orange. 

Perennial, from branching rootstocks ; bristles green, yellowish green or 
* purple. 
Inflorescence stout : bristles usually exceeding twice the length of the 
spikelet. 
Rootstocks slender : leaf-blades elongated. 

Second scale of the spikelet 5-7-nerved : leaf-blades sometimes with 

a few scattered hairs near the base on the tipper surface. 2. C. imberbis. 

Second scale of the spikelet 3-nerved : leaf-blades glabrous. 3. C\ versicolor. 

Rootstocks stout : leaf-blades short, thick and firm, grayish green. 4. C. occidentalu. 

Inflorescence slender : bristles once or tAvice as long as the spikelet. 
Leaf-blades linear-lanceolate, short. 
- _ Leaf-blades linear, elongated, 

inflorescence with the spikelets in clusters or on branches : bristles 1-3 at the base 

of each spikelet. not involucrate. 
Bristles downwardly barbed. 
Bristles upwardly barbed. 

a. Second scale of the spikelet as long as the flowering scale or very nearly so. 
* Panicle thick, dense, its branches crowded. 

Flowering scale dull, papery when mature, often finely transversely 
rugose : plants usually less than 1.5 m. tall. 
Panicle usually 1 cm. thick or less : bristles commonly green : spike- 
lets about 2 mm. long. 



1. C glauca. 



5. C, pnrpura8C€7is. 

6. C. gracUU, 



7, C verticiilata. 



8. C. inridis. 



lOG 



POACEAE 



9. C. Italica. 

10. C. magna, 

15, C. viUosissima. 

16. C, Grisehachii. 



13. C. mdcrostachya. 



11. C. corrugata. 

12. r*. compodia. 



12. C. composita. 



Panicle usually 1-3 cm. thick : bristles usually purple : spikelets 
2.5-3 mm. long. 
Flowering scale shining, very hard m fruit, smooth : plants usually 

2-4 m. tall. 
** Panicle slender, loose, narrow, often interrupted below. 
Spikelets about 3 mm. long. 
Spikelets about 2 mm. long. 
b. Second scale manifestly shorter than the flowering scale. 
Spikelets less than 3 mm. long. 

Panicle loose, often interrupted below, usually narrowed at the summit. 
Spikelets elliptic to ovate. 

Panicle long-attenuate at the apex. 18. C. candata. 

Panicle narrowed at the apex, but not long-attenuate. 

Leaf-blades 1 cm. wide or less : stems usually slender. 16. C. GrL-iebachii. 

Leaf-blades 1.5-2 cm. wide: stems usually stout. 17. C pohjstachya, 

Spikelets hemispheric. 
Panicle dense, of the same diameter throughout. 

Flowering scale very coarsely unduiate-rugose : panicles with many 

bristles, 
Flow^ering scale finely transverse-rugose ; panicles with rather few 
bristles. 
Spikelets 3 mm. long or more. 

Panicle dense, of equal diameter throughout, 1 cm. thick or less, ex- 
clusive of the bristles. 
Panicle loose, narrowed at the summit, 2-4 cm. in diameter, exclusive 
of the bristles. 
Leaf- blades 1-2 cm. wide, glabrous. 14. C. macrosperma. 

Leaf-blades 6-8 mm. wide, pubescent on both surfaces with spread- 
ing hairs. 15. C. villodssima. 

1. Chaetochloa glauca (L.) Scribn. Annual. Stems tufted, 3-12 dm. tall, branch- 
ing at the base : leaf-slieaths glabrous, loose, compressed ; blades 1.5 dm. long or less, 4-8 
mm. wide, glaucous, at least the lower ones pilose near the base on the upper surface : ra- 
cemes dense, about 1 cm. in diameter, the rachis pubescent, 2-10 cm. long : spikelets 
broadly ovoid, 3 mm. long and 2 mm. wide, the acute flowering scale striate, coarsely 
transversely rugose. ISetaria ylauca Beauv. ] 

In cultivated grounds and waste places nearly throughout North America. Naturalized from 
Europe. Summer and fall. * 

2. Chaetochloa imb^rbis (Poir.) Scribn. Perennial. Stems tufted, 3-7 dm, tall, 
from rootstocks, slender, compressed, rough below the raceme : leaf-isheaths glabrous, com- 
pressed ; blades 1-3 dm. long, 3-7 mm. wide, the upper surface often with a few long hairs 
at the base : racemes dense, si)ike-like, 2-5 cm. long, nearly 1 cm. in diameter, exclusive 
of the bristles, the rachis pubescent : bristles 5-10 mm. long : spikelets ovoid, acute, 2-2.5 
mm. lon^, the flowering scale acute, striate, finely transversely rugose. [Setaria laevigata 
Chapm. m part. ] 

In moist soil, New Jersey, Kansas and Missouri to Florida and Texas. Also in tropical America. 
Spring to fall. 

3 Chaetochloa versicolor BicknelL Perennial. Stems 6-12 dm. long, ascending : 
leaf -sheaths compressed, keeled, smooth and glabrous ; blades long and narrow, 1-3.5 dm. 
long, 2-6 mm. wide, pale green or glaucous, glabrous : spike-like raceme long-exserted, 
rather slender, 2-7 cm. long, about 1.5 cm. in diameter : bristles in two nearly equal clus- 



w 



ters of 5 each, very slender, 6-10 mm. long: spikelets usually single, about 2.5 mm. long 
and 1.25 ram. wide, the first and second scales 3-nerved, the fourth scale purple-tipped. 
[Pamcum laevigatum Ell., not Lam. Setaria laevigata Chapm. in part.] 

Along borders of salt or brackish marshes, Massachusetts to Florida. Summer and fall. 

4. Chaetochloa occidentilis Nash. Perennial. Stems from a stout branching root- 
stock, 3-8 dm. tail : leaf -sheaths compressed, keeled, smooth and glabrous ; blades erect^ 
firm, 1.5 dm. long or less, 5-7 mm. wide, glabrous : spike-like racemes 3-5 cm. long, 1-^ 
2 cm. in diameter : bristles green : spikelets a little less than 3 mm. long, the flowering 
scale strongly transversely rugose, elliptic. 

In meadows, Kansas and the Indian Territory. Summer. 

5. Chaetochloa purpurdscens (H.B.K.) Scribn. & Mer. Perennial. Stems 1-6 
dm. tall, slender, branching, from rootstocks : leaf-sheaths loose, striate, glabrous ; blades 
5-10 cm. long, 4-6 mm. wide, rough on both surfaces : racemes 1-5 cm. long, about 5 mm. 
in diameter, the rachis pubescent : bristles 5-10, 3-8 mm. long, often barely exceeding tne 
spikelets : spikelets ovoid, acute, 2 mm. long, the flowering scale acute, transversely ru- 
gose. 

In dry places, Texas. Also in tropical America. Spring to fall. 

6. Chaetochloa gr^cilig (ILB.K.) Scribn. & Mer, Perennial. Stems erect, 3-7 
dm. tall, slender, cylindric, simple, or somewhat branched at the base : leaf-sheaths loo^^^ 



glabrous ; blades involute-setaceous, 2 dm. long or less, 1-3 mm. wide : racemes dense, -^ 
6 cm. long, 3-5 mm. in diameter: bristles 5-8, very short, equalling or twice as long 



POACEAE 



107 



the spikelet : spikelets 2 mm. long, ovoid, acute, the flowering scale acute, abruptly 
apiculate, transversely rugose. [Seiaria imberbis Chapm.] 

In sandy soil, Texas, and adventive eastward. Also in tropical America. Spring to fall. 

7. Chaetochloa veiticillkta (L.) Scribn. Annual. Stems 3-6 dm. tall, erect or 
ascending : leaf -sheaths loose, the margin ciliate above ; blades 7-18 cm. long, 6-12 mm. 
wide, flat, rough on both sides : panicle spike-like : bristles 1-3, stout, flexuous, 3-0 mm. 
long : spikelets narrowly elliptic-ovate, acute, 2-2.5 mm. long, tlie flowering scale about 2 
mm. long, rounded at the shortly apiculate apex, smooth, or with very fine transverse 
wrinkles below the middle. [Seiaria verticillaia Beauv.] 

In waste places, fields and along roadsides, throughout the United States. A cosmopolitan weed. 
Introduced from Europe. Summer and fall. 

8. Chaetochloa viridis (L. ) Scribn. Annual. Stems tufted, usually much branched 
at the base, compressed, 2-9 dm. tall : leaf -sheaths compressed, loose, ciliate on the margin ; 
blades 3 dm. long or less, 4—10 mm. wide : spike-like panicles 2-10 cm. long, about 1 cm. 
in diameter, exclusive of the bristles, green, the rachis villous: bristles 1-1.5 cm. long: 
spikelets about 2 mm. long, elliptic, the flowering scale elliptic, rounded at the apex, finely 
and faintly transversely rugose below the middle or merely striate and pitted. [Setaria 
viridis Beauv. ] 

In cultivated grounds and waste places nearly throughout North America. Introduced from 
Europe. Summer and fall. 

9. Chaetochloa It^lica (L. ) Scribn. Annual. Stems simple, or branched at the 
base : leaf-sheaths loose, glabrous, ciliate on the margin ; blades long-acuminate, 2-4 dm. 
long, 1.5-3 cm. wide, rough: panicles dense, cylindric, 8-20 cm. long, 2-3 cm. in diam- 
eter, obtuse or truncate at both ends, the rachis densely villous : bristles 1-3, 3-10 mm. long, 
often shorter than the spikelets or nearly wanting : spikelets elliptic, 2.5-3 mm. long. 

In fields and waste places, Quebec and Minnesota to Florida and Texas. AVidely cultivated and 
very variable. Introduced from Europe or Asia. The variety (7. liallca Germdnica (Mill.) Scribn. 
differs in being smaller and more slender, and in having a smaller narrower panicle which is usually 
tapering at the base. Italian Millet. Hungarian Grass. 

10. Chaetocbloa mdgna (Griseb. ) Scribn. Stems stout, erect, 1-4 m. tall, branch- 
ing at the base : leaf-sheaths glabrous, compressed; blades 3-6 dm. long, 1-3 cm. wide, 
rough : panicle usually interrupted below, 1-3.5 dm. long, 2-5 cm. in diameter ; bristles 
l~2j green, 8-11 mm. long: spikelets elliptic, acute, 2 mm. long. [&/aria ma </na Griseb.] 

In swamps or even in shallow water, Delaware to Florida, Louisiana, and Texas. Also in tropical 
America. Summer and fall. 

11. Chaetochloa corrugata (Ell.) Scribn. Annual. Stems tufted, 5-10 dm. tall, 

compressed, much branched at the base, sometimes rooting at the lower nodes : leaf-sheaths 
very loose, compressed, keeled ; blades 1-3 dm. long, 3-6 mm. wide, rough, narrowed to- 
ward both ends : panicle 5-15 cm. long, 5-15 mm. in diameter, exclusive of the bristles : 
bristles solitary or rarely 2 at each spikelet, 5-15 mm. long : spikelets ovoid, acute, about 
2 mm. long, the fourth scale very strongly transversely and coarsely undulate-rugose. 
[Seiaria corrugata Schult. ] 

In fields and waste places, Georgia and Florida. Summer and fall. The variety C. rorrufjata 
parvifldra (Poir.) Scribn. & Mer. is a more slender and short form with shorter leaf-blades and panicles. 
In similar situations, South Carolina to Florida. Also in the West Indies. Spring to fall. 

12. Chaetochloa compdsiCa (II.B.K. ) Scribn. Perennial. Stems tufted, 3-10 
dm. tall, much branched from 1 




glabrous ; blades linear 

pale green, 5-15 cm. long, 5-15 mm. in diameter, exclusive of the bristles : bristles singk», 
rarely in pairs, green, flexuous, 5-15 mm. long: spikelets narrowly ovoid, 2-3 mm. long, 
the flowering scale narro^y ovoid, acute. 

In dry soil, Colorada to Arizona and Texas. Also in tropical America. Summer and fall. 

13. Chaetochloa macroat^chya (H.B.K. ) Scribn. & Mer. Perennial. Stems erect 
or ascending, 6-12 dm. tall, rather stout, compressed : leaf-sheaths loose, glabrous or nearly 
; blades linear-lanceolate, rigid, 1.5-5 dm. long, 1-1.5 cm. wide, usually roufjh, gener- 



erally with a few long white hairs near the base: panicle pale ^reen, strict, usually taper 
ing at the apex, 1-3 dm. long, 1-2 cm. in diameter : bristles single or in pairs, slender, 
flexuous, 1-2 cm. long : spikelets ovoid-globose, about 2 mm. long, acute, the flowering 
scale strongly convex, apiculate, transversly nndulate-ru^ose. 

In dry soil, Texas. Also in tropical America. Spring to fall. 

14. Chaetochloa macrosp^rma Scribn. & Mer. Perennial. Stems stout, 6-12 dm, 
tall, glabrous : leaf-sheaths compressed, glabrous, the margins ciliate ; blades linear-lanceo- 
late, 1-3 dm. long, 1-2 cm. wide, rough or smooth : panicle 1-2.5 dm. long, 2-4 cm. in 
diameter, exclusive of the bristles : bristles single, 1.5-3 cm. long, green : spikelets n:ir- 



lOS 



PUACEAE 



ruw'Iy ovoidj ucute, 3 mm. long, the flowering scale acute, narrowly ovoid, finely trans- 
versely rufjose. 

On shell islands or keys, or sometimes in old fields, southern Florida and Texas. Summer to fall. 

15. Chaetochloa villosissima Scribn. & Mer. Perennial. Stems branching at the 
ba^se, 4-10 dm. tall, compressed, glabrous : leaf-sheaths loose, compressed, rough above, 
nearly smooth below, densely villous above ; blades linear, 1.5-3 dm. long, 6-8 ram. wide, 
tapering toward the base, pubescent on both surfaces with Avhite spreading hairs : panicle 
about 2 dm. long, 2-8 cm. in diameter, tapering to the apex : bristles single, green, 1.5-2,5 
cm. long : spikelets ovate-lanceolate, acute, 2.5-3 mm. long, the flowering scale abruptly 
short-apiculate at the incurved tip, rather finely transversely rugose below and punctate 
above. 

In dry soil, Texas. Spring and summer. 

16. Chaetochloa Griaebdchii (Fourn. ) Scribn. Annual. Stems 1.5-8 dm. tall, 

branching at the base, slender, glabrous : leaf -sheaths loose, compressed, sparingly strigose, 

the margins ciliate ; blades lanceolate, slightly narrowed at the cordate base, 5-10 cm. 

long, 5-10 nun. wide, rough and sparingly short-pubescent : bristles single or in pairs, 

widely spreading, purple or sometimes green, 5-15 mm. long : spikelets ovoid, 2 mm. long, 

acute, the flowering scale nearly 2 mm. long, ovoid, acute, very finely transversely rugose 
below. 

In dry soil, Texas to Arizona. Also in Mexico. Spring to fall. 

17. Chaetochloa polys'-Achya (Scheele) Scribn. & Mer. Perennial. Stems stout, 
6-12 dm. tall, branching at the base, glabrous: leaf-sheaths glabrous or sparingly pubes- 
cent, the margins ciliate : blades 1.5-3 dm. long, 1.5-2 cm. wide, abruptly narrowed at the 
base, rough, the lower ones sometimes strigose : panicle lax, pale green, 1.5-3 dm. long, 
1.5-3 cm. in diameter: bristles single, 8-12 mm. long, green, slender, flexuous : spikelets 
narrowly ovoid, acute, 2 mm. long, the flowering scale narrowly ovoid, acute, transversely 
undulate-rugose at the base. 

In dry soil, Texas. Summer and fall. 

18. Chaetochloa catidata (Lam.) Scribn. Annual. Stems 3-6 dm. tall, much 
branched from the l)ase, glabrous, slender : leaf-sheaths pubescent, ciliate on the margin ; 
blades linear, 1-3 dm. long, 3-5 mm. wide, pubescent, filiform-attenuate at the apex: 

Sanicle 5-15 cm. long, attenuate, the rachis slender and flexuous, pilose : bristles single, 
exuous, 4-10 mm. long: spikelets ovoid, acute, the flowering scale ov^oid, acute, short- 
apiculate, transversely undulate-rugose below. 

In dry soil, New Jersey to Florida and Alabama. Also in tropical America. Spring to fall. 

36. CENCHRUS L. 

Annual or perennial grasses, witli flat, convolute orcomplanate leaf -blades and terminal 



/ 



spikes. Spikelets 2-6, in an ovate or globose involucre, consisting of two thick hard 
valves which are exteriorly armed Avith stout spines and sometimes also with basal bristles 
which are thickened at the base, the involucres articulated to the rachis and readily de- 
ciduous, carrying the persistent spikelets with them. Scales 4, awnless, the first and sec- 
ond empty, the fii-st small or minute, the third equalling or longer than the second, enclos- 
ing a palet and also sometimes a staminate flower, the fourth scale chartaceous, firmer, 
enclosing a palet of similar texture and a perfect flower. Stamens 3. Styles often connate 
at the very base. Stigmas plumose. Bur Grass. Sand Bur. Sand Spur. CocKsruR. 

Involucre armed at the base : 

With shorter generally reiiexed spines, the base of the involucre glabrous : in- 
volucres containing 2 spikelets. 
Involucre pubescent : 

Usually less than 5 mm. broad. 
6-8 mm. broad. 
Involucre glabrous. 
With erect barbed bristles, the base of the involucre \illous: involucres con- 
taining 4-6 sjiikelets. 
Involucre naked at the base. 

1. Cenchrus tdbuloides L. Stems at first erect, later prostrate and forming mats, 
'>-rt Hni Inno- hrnnphino- • Ipnf-shefttbs eomnressed ! blades 6-12 cm. loner. 4-S mm. wide, 



1. a tribuloides, 

2. C. macrocephalus, 

3. C graciUimus. 

4. C. echwatus. 

5. C. incertus. 



6-20 



3-4 



bev 



In dry sandy places. Massachusetts, Ontario, Minnesota and Nebraska to Florida, Texas and 
Mexico. Verv variable. Spring to fall. 



l^OACEAE 



109 



2. Cenchrus inacroc6phalus (Doell) Scribn. Stems at lii*st erect or ascending, later 
becoming prostrate and branched and forming mats, 3-6 dm. long: leaf-sheaths verv 
loose, glabrous, compressed ; blades flat or complanate, smooth and glabrous, 1 dm. loi^g 
or less, 4-8 mm. wide: spikes stout, 3-5 cm. long: involucres 5-12, 6-8 mm. broad, en- 
closing 2 spikelets, pubescent, the spines usually 5-8 mm. long :' s])ikelets not exserted be- 
yond the involucre. 

Along the seashore, New Jersey to Mississippi. Summer and fall. 

3. Cenchrus gracillimus Nash. Stems erect or ascending, 3-6 dm. tall, simple, or 
sometimes sparingly branched above, slender : leaf-sheaths but little inflated ; l)lades com- 



planate, 5-8 cm. long, about 2 mm. wide, acuminate : si)Ike8 finally long-exserted, 3-5 cm. 
long, bearing 3-6 distant purplish involucres which are glabrous and with a deeply fur- 
rowed and glabrous base, the spines purple, 5-6 mm. long : spikelets about 8 mm. long, 
exserted beyond the involucre from |-^ their length. 

In dry sand in the high pine laud region, peninsular Florida. Spring and summer. 

4. Cenchrus echinatus L. Stems finally prostrate and rooting at the nodes, 
branched: leaf-sheaths loose; blades 1-4 dm, long, 5-15 mm. wide, smooth or rougli, 
flat : spikes 4-12 cm. long, finally more or less exserted : involucres 20-50, densely crowded, 
containing 4-6 spikelets, glabrous, green to purplish, pubescent, villous at the base, the 
spines 3-4 mm. long, the bristles at tlie base numerous, slender, distinctly barbed for their 
whole length : spikelets 6-7 mm. long, exserted from the involucre. 

In sandy places, North Carolina to Florida and Texas. Also in tropical America. Spring to fall. 

5. Cenchrus inc^rtus M. A. Curtis. Stems at fii-st erect or ascending, finally pros- 
trate and rooting at the lower nodes, 3-6 dm. long : leaf-sheaths compressed, inflate<l ; 
blades glabrous, flat, 4-15 cm. long, 3-5 mm. w^de : spikes usually exserted, 3-6 cm. long : 
involucres 8-20, containing 2 spikelets, pubescent, ovoid, glabrous at the base, the spines 
about 3 mm. long, very broad at the base, ciliate : spikelets 5 mm. long, exserted from the 
involucre. 

In dry sandy places, South Carolina to Florida and Texas. Summer and fall. 

37. CBNCHROPSIS Nash. 

Perennial grasses, with long rootstocks, flat leaf-blades and terminal spicate inflores- 
cence. Spikelets single, subtended by an involucre consisting of 1 or 2 outer rows of 
barbed bristles Avhich are thickened at the base, and 1 or 2 inner rows of barbed spines 2-4 
times as long as the bristles and about equalling tlie spikelet, the involucre articulated to 
the rachis and readily deciduous. Scales 4, the first and second empty, the first about one- 
half as long as the spikelet, the third scale longer than the second, enclosing a palet one- 
half its length or less, the fourth scale cliartaceous, firmer, enfolding a palet of similar 
texture and a perfect flower. Stamens 3. Styles often connate at the very base. 

1. Cenchropsis myosuroidea (II.B.K.) Nash. Stems 6-14 dm. tall, from a stout 
rootstoek, simple, or branched above : leaf-sheaths glabrous ; blades glabrous, 1-3 dm. 
long, 3-8 mm. wide : spikes 5-20 cm. long, included at the base or exserted : involucres 
numerous, consisting of 1-2 rows of barbed spines as long as the single spikelet, and sub- 
tended by 1-2 rows of barbed bristles J-J as long: spikelets about 5 ram. long. [Cenchrnfi 
myomroides H.B.K.] 

In dry sandy places, Georgia and Florida. Also in tropical America. Spring to fall. 

38. PENNISETUM Pers. 

Annual or perennial, often branched, grasses, with flat leaf-blades and terminal den.se 
cylindric spikes. Spikelets in l's-3'8, 1-2-flowered, subtended by an involucre consisting 
of numerous slender bristles which are not tliickened at the kise, all the bristles, or at least 



the middle ones, plumose. Scales 4, rarely 3, the 2 outer empty, the first small or minute, 
rarely wanting, the second often as long as the spikelet, the third scale empty or enclosing 
a palet and a staminate flower, the fourth scale firmer, shorter, enfolding a palet of similar 
texture and a perfect flower. Stamens 3. Styles usually distinct. Stigmas plumose. 

1. Pennisetum setosum (Sw.) Pers. Stems 1-1.5 ni. tall, simple or branched : leaf- 
sheaths glabrous, keeled ; blades 3 dm, long or less, 6-13 inm. wide, long-acuminate, the 
upper surface toward the ba.se pubescent with long spreading stout hairs : spikes dense, 
cylindric, 1-3 dm. long, 1-1.5 cm. in diameter: bristles of two kinds, the outer short and 
slender, merelv hisnidulous. about as lonsr as or sluu-ter than the spikelet, the inner much 






110 



POACEAE 



longer, stouter, beautifully plumo.se below : spikelets very numerous, densely crowded, 
about 4 mra. long. 

In damp places, southern peninsular Florida. Also in tropical America. Summer and fall. 
MlssionGp.a^.s. 

39. PENICILLARIA Beauv. 

Tallgras^ies, witb flat leaf-blades and dense cylindric panicles. Spikelets in pairs on a 
sliort pedicel, surrounded by bristles, persistent ; bristles little if at all exceeding the spike- 
lets, the outer ones short and merely hispidulous, the inner ones plumose. Scales 4, the 
3 outer membranous, the fourth scale shorter, firmer, enclosing a palet of similar texture 
and a perfect flower. Stamens 3. Styles usually distinct. Stigmas plumose. 

1. PenicUlaria spic^ta (L. ) Willd. Stems erect, 1 m. tall or more, densely and softly 

{)ubescent below the inflorescence, leafy : leaf-sheaths strongly ciliate on the margins with 
ong hairs ; blades 4 dm. long or less, 6-10 mm. wide, long-acuminate : panicles 1-3 dm. 
long, cylindric, 1-1.5 cm. in diameter: outer bristles shorter than the spikelet, numerous, 
slender, merely hispidulous, the inner ones stouter, few, about equalling the spikelet in 
length, plumose : spikelets about 4 mm. long. 

In fields and waste places, and along i roadsides, Alabama and Mississippi. Summer and fall. 

40. STENOTAPHRUM Trin. 

Perennial grasses, creeping and branching at the base, with compressed stem, flat or 
convolute leaf -blades, and a terminal spike or spike-like panicle. Spikelets acute or acumi- 
nate. 2- (rarely 1-) flowered, in 2's-4's in short spikes which are embedded in the alternate 
notches on one side of the broad and compressed rachis. Scales 4, rarely 3, the 2 outer 
empty, the first small, rarely wanting, the second equalling or a little shorter than the 
spikelet, the third scale similar to the second, enclosing a palet and a staminate flower, 
nirely empty, the fourth scale more rigid than tlie others, enfolding a palet of similar 
texture and a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. 

1. Stenotaphrum secundcLtum (Walt.) Kuntze. Stems compressed, prostrate and 
rooting at the lower nodes : leaf -sheaths compressed, glabrous, keeled ; blades flat, or 
folded when dry, linear, rounded at the apex, usually less than 1 dm. long, sometimes 
longer, 4-10 mm. wide : spikelets 5-10 mm. long, immersed in one side of a broad com- 
pressed rachis, 3.5-5 mm. long. 

In sandy soil, South Carolina to Florida and Texas. Also in tropical America. Spring to fall. 
Shoke Grass. 

41. OLYRA L. 

Usually tall grasses, with broad flat leaf-blades, which are contracted into a petiole- 
iike base, and terminal or axillary panicles. vSpikelets unisexual, monoecious : staminate 
spikelets arranged along the panicle branches below the summit ; scale 1, usually awned ; 
palet as long as the scale, 2-neryed ; stamens 3. Pistillate spikelets terminating the main 
branches of the panicle, much larger than the staminate ; empty scales 2, usually awned, 
membranous, the tliird scale chartaceous, indurated in fruit ; styles 2, united at the base. 

1. Olyra latifoHa L. Stems finally branched : leaf -blades contracted at their junc- 
tion with the sheath into a petiole-like base, oblong to broadly lanceolate, rather abruptly 
acuminate, the primary ones 1.5 dm. long or less, 2-4 cm. wide : panicle triangular or 
ovate, its branches spreading or ascending : staminate spikelets lanceolate, 4-5 mm. long, 
exclusive of the awn : pistillate spikelets ovoid, acuminate, 8-10 mm. long, exclusive of 



the awn. 

In dry places, southern peninsular Florida. Also in tropical America. Summer. 

42. HYDROCHLOA Beauv. 

Slender branching monoecious aquatic grasses, usually floating, sometimes creeping, 
with narrow flat leaf-blades and spicate inflorescence. Spikelets small, of two kinds, the 
staminate in a slender short terminal spike, the pistillate in few-flowered spikes in the upper 
leaf-axils^ the spikes but little exserted from the sheaths. Scales 2, a little unequal, mem- 
branous, concave, awnless, palet wanting. Stamens 6. Styles short, distinct, somewhat 
laterally attached to the apex of the ovary. Stigmas elongated, shortly plumose. 



POACEAE 



111 



1. Hydrochloa fluitans (Michx.) Nash. Floating or creeping. Stems 1 m. long or 
lesy, slender, much branched : leuf-sheaths sparingly pilose at the summit ; blades 1-4 cm. 
long, 1.5-4 mm. wide: staminate spikelets 4.5-5 jnm. long: stamens about 3 mm. long: 
pistillate spikelets about 2.5 mm. long. 

In water or on muddy banks, North Carolina to Florida. Summer and fall. 

43. PHARUS L. 

Monoecious, usually tall, grasses, with ample i)anicleH and large oblique long-petiolate 
feather-veined leaf-blades with numerous veinlets, the petioles twisted, hence reversing the 
leaf. Spikelets articulated below the scales, of two kinds, in pairs upon the branches of 
the paniclcj one sessile, pistillate, the other much smaller, pedicellate, staminate. Scales 
3 ; in the staminate spikelets membranous, somewhat broadened, the 2 outer empty, the 
first a little shorter, the second longer than the flowering scale ; the third scale en- 
closing a floAver but no palet ; in the pistillate spikelets the outer two scales membranous, 
empty, many-nerved, subequal, the third scale much longer than the others, narrow, 
at length indurated, nearly closed by the involute margins, enfolding a 2-toothed mem- 
branous palet which is convolute around the flower. Stamens 6. Styles filiform, elongated, 
united to near the apex. Stigmas papillose. 

1. Pharus latifolia L, A leafy perennial. Stems 6 -10 dm. tall : leaf -sheaths longer 
than the internodes, concealing the stems ; petiole-Iike base of the blades 1-5 cm. long ; 
blades oblanceolate to elliptic, acute, commonly 1-2 dm. long, 3-4 cm. wide; panicle 1-2 
dm. long, its branches finally widely spreading : sessile spikelet about 9 mm. long, the 



empty scales brown, acute, the flowering scale about twice as long as the empty ones 
cyhndric, about 1.5 mm. in diameter, densely pubescent with spreading glandular-tipj^ed 
hairs, abruptly acute at the naked apex ; pistillate spikelet 3-5 mm. long, the apex about 
reaching the summit of the sessile spikelet. 

In hammocks, near Orange Lake, Florida. Summer. 

44. LUzfoLA Juss. 

Creeping monoecious marsh or aquatic grasses, with flat leaf-blades and open terminal Oj. 
lateral panicles, Spikelets small, articulated below the scales, 1 -flowered, the staminate 
and smaller pistillate in separate panicles. Scales 2, awnless ; in the staminate spikelet 
thin-membranous, the first empty, broader but scarcely shorter than the second which en- 
closes a flower but no palet ; in the pistillate spikelet membranous, the first scale striately 
many-nerved, broader than the second which encloses a flower. Stamens 6-18. Styles 
short, distinct. Stigmas plumose with simple hairs, 

Staminate and pistillate spikelets borne in panicles on different stems : pistillate 

spikelets less than 3 mm. long. 1. L, Peruviana. 

Staminate and pistillate spikelets borne in separate panicles on the same stem: 

pistillate spikelets about 4 mm. long. 2. L. Alahamensis, 

1. Luziola Peruviana Pers. Stems finally branching and rooting at the lower 
nodes, 4 dm. long or less : leaf-blades elongated and narrow : staminate panicles 3-6 cm. 
long, the branches erect, the spikelets about 6 mm. long : pistillate panicles 4-6 cm. long, 
the branches spreading or ascending, the spikelets 2-2.6 mm. long. 

In ditches and in wet usually grassy places, Louisiana. Summer and fall. 

2, Luziola Alabam^nsis Chapm. Stems finally branching and rooting at the lower 
nodes, 1-3 dm. long : leaf-blades elongated and narrow, usually much exceeding the pan- 
icles : panicles 3-8 cm. long, often included below in the upper leaf-sheath, the branches 
commonly ascending or erect : staminate spikelets 5-6 mm. long : pistillate spikelets about 
4 mm. long. 

In wet places, Alabama and Mississippi. Summer and fall. 

* 

45. ZIZANIOPSIS Doell & Aschers. 

Tall robust perennial monoecious aquatic grasses, with creeping rootstocks, long flat 
leaf -blades and ample terminal panicles. Spikelets with a more or less prominent carti- 
laginous ring at the base, 1-flowered, narrow, articulated below the scales, flattened, of 2 
kinds, the staminate at the base of, the pistillate terminating, the branches of the narrow 
panicle. Scales 2, membranous, concave, acute, the first empty, awned in the pistillate 
spikelets, a little broader than the scarcely shorter awnless second scale which encloses a 
flower but no palet. Stamens 6. Styles united, i^tigmas plumose with short hairs. 



112 



POACEAE 



1. Zizaniopsis miliacea (Miclix. ) Doell & A*<cliers. Stems 1-4 m. tall, from a long 
and creeping rootstock : leaf-slieatlis smooth and glabrous ; blades 3-10 dm, long, 1-3 
cm. wide, usually smooth and glabrous : panicle 2.5-6 dm. long : staminate spikelets 7-S 
mm. long, more or less awned ; pistillate spikelets 5-6 mm. long, the awn 2-6 mm. long. 



In swamps, Georgia and Ohio to Florida and Texas. Summer. AVater Millet. Mahsh Millet. 



46. ZIZANIA L. 

Tall robust annual monoecious aquatic grasses, with broad flat leaf-blades and ample 
terminal panicles. Spikelets of two kinds, articulated below the scales, 1-flowered, each 
with a more or less prominent cartilaginous ring at the base, narrow, the staminate readily 
deciduous, on the more or less spreading lower branches, the pistillate tardily deciduous, on 
the erect or appressed upper branches of the panicle. Scales 2, the first empty, the second 
enclosing a flower but no palet : scales of the staminate spikelets membranous, concave, 
acute or aVn-pointed ; those of the pistillate spikelets linear, firmer, involute, the first 
long-awned, longer than the awm-pointed second. Stamens 6. Styles nearly distinct. 
Stigmas plumose with short hairs. 

1. Zizania aquitica L. Annual. Stems 1-3 m. tall : leaf-sheaths smooth and gla- 
brous ; blades 1,5-8 dm. long, 5-25 mra. broad, usually rough: panicle 2-3 dm. long: 
staminate spikelets 7-8 mm, long : pistillate spikelets 12-20 mm. long, the awn 2.5-5 cm. 
long. 

In swamps and along creeks and rivers. New Brunswick to Manitoba, Florida, Louisiana and 
Texas. Summer and Fall. Indian Rice. Wild Rice. Reeds. Water Oats. Marsh Rice. 



47. ORYZA L. 

Swamp grasses, with flat leaf-blades and terminal narrow panicles, the branches of 
which are slender, erect and somewhat flexnous. Spikelets much compressed, articulated 
below the empty scales, 1-flowered. Scales 4, the 2 outer empty, very small, scale-like or 
bristle-form, the 2 inner compressed-keeled, somewhat rigid, the first a little the larger, 
empty, awned or awnless, the keel often narrowly winged or muricate, the second scarcely 
shorter, narrow^er, short -awned or awnless, the keel not winged, naked, enclosing a perfect 
flower but no palet. Stamens 6. Styles short, scarcely united at the base. Stigmas 
plumose with short hairs. 

1. Oryza sativa L. Stems 5-10 dm. tall or more, simple : leaf-blades usually 
rough : panicle 1-3 dm. long, its branches erect : spikelets 8-10 mm. long, oblong, hispid, 
sometimes awned. 

In ditches and water, Virginia to Florida and Texas. Extensively cultivated. Native of tropical 
Asia. Summer and fall. Rice. Rice Grass. > Cut Grass. 

48. HOMALOCENCHRUS Mieg. 

T 

Grasses of wet situations, with flat leaf-blades and usually open, rarely contracted, ter- 
minal panicles, the branches of which are slender. Spikelets often with a cartilaginous 
ring at the base, articulated below the scales, compressed, 1-flowered. Scales 2, compressed- 
keeled, somewhat rigid, awnless, the first scale empty, usually ciliate on the keel, broader 
than the second which encloses a perfect flower but no palet. Stamens 1-6. Styles short 
or slender, distinct. Stigmas plumose wuth branched hairs. [Leersia Sw., not Hedw.] 

Spikelets oblong to elliptic, their width less than % their length. 

Spikelets glabrous, 2 mm. long or less : stamen 1 : stems densely tufted, erect. 1. H, monandru^.- 

Spikelets aculeate on the keels, hispidulous on the surface, 2.5 mm. long or more : 
stamens 2 or more : stems decumbent at the base. 
Panicle-branches singly disposed, few, usually less than 8. 

Panicle-branches elongated, each with a long naked base; stamens 2. 2. 11. Virginicus. 

Panicle-branches short, spikelet-bearing to the base ; stamens 6. 3. H. hcxandrus. 

Panicle-branches, at least the lower ones, in whorls or approximately in pairs, 

numerous, usually exceeding 15. 4. Jf. oryzoidcs. 

Spikelets broadly oval to nearly orbicular, their width more than % their length. 5. //. lenticiilaris. 

1. Homalocefichrus monindrus (Sw. ) Knntze. Stems densely tufted, 4-6 dm. tall : 
leaf-sheaths smooth and glabrous ; blades erect, 4-15 cm. long, 2-5 mm. wide, roughish : 
panicle 7-13 cm. long, its branches ascending, slender, 3-4 cm. long : spikelets 1.75-2 mm. 
long, about 1 mm. broad, smooth and glabrous : stamen 1. 

In dry soil, extreme southern parts of Florida and Texas. Also in tropical America. Spring. 



POACEAE 



113 



Homalocenchrus 



Virginicus (Willd.) Britton. Stems 6-13 dm. tall, slender, 
pubescent at the nodes, finally much branched : leaves rough ; blades erect or ascending, 3- 
20 cm. long, 2-11 mm. wide : panicle 6-20 cm. long, its branches finally spreading, slender, 
4-9 cm. long, single at the nodes: spikelets 2.5-3.5 mm. long, 1-1.3 mm. broad, aculeate 
on the keels, hispidulouson the surface : stamens 2. 

In moist places and low woods, Maine and Ontario to Dakota, Florida and Texas. Sprinc to fall 
Whitk Grass. 

3. Homalocenchrus hexdndrus (Sw. ) Kuntze. Stems slender, weak, 6-10 dju. long, 
rooting at the lower nodes : leaves exceedingly rough; blades flat, erect, 3-15 cm. long, 
3-6 mm. wide : panicle 4-8 cm. long, its branches ascending, 1.5-4 cm. long : spikelets 
4-4.5 mm. long, 1.25-1.5 mm. broad, the keels strongly aculeate, the haii>i increasing in 
length toward the apex, the surface of the scales hispidulous : stamens 6. 



In water, North Carolina to Florida and Texas. Also in tropical America. Spring and summer. 

4. Homalocenchnis oryzoides (L. ) Poll. Stems 8-15 dm. tall, often rooting at the 
lower nodes : leaves very rough ; blades 6-20 cm. long, 5-13 mm. wide, ascending: panicle 
1-2 dm. long, often partially included at the base, its branches ascending or spreading, the 
longer 6-10 cm. long : spikelets 4-4.5 mm. long, about 1.5 ram. broad, the keels aculeate, 
the surface hispidulous : stamens 3. 

In wet places and swamps, Nova Scotia and Ontario to Washington, Florida, Texas and California. 
Also in Europe and Asia. Summer and fall. Rice Cut Grass. 

5. Homalocenchrus lenticul^ris (Michx. ) Scribn. Stems 2-12 dm. tall: leaves 
rough ; blades 8-30 cm. long, 8-20 mm. wide : panicle 6-20 cm. long, its branches spread- 
ing, 2-8 cm. long : spikelets 4.5-5 mm. long, 3-3.5 ram. broad, keels strongly aculeate, the 
surface glabrous or sparingly hispidulous : stamens 2. 

In marshes and wet places, Virginia to Florida, and from Illinois and Missouri to Louisiana. 
Summer and fall. Catch-fly Grass. • 

49. PHALARIS L. 

Annual or perennial grasses, with flat leaf -blades and terminal panicles which are cylin- 
dric and spike-like, capitate, or densely thyrsoid and somewhat interrupted. Spikelets 
articulated above the empty scales, compressed, 1-flowered, crowded. Scales 5, the 2 lower 
persistent, larger than the rest, thin-paleaceous, com[)ressed-keeled, the keel usually more 
or less winged, sometimes wingless, awnless, tliird and fourth scales shorter, very thin and 
narrowly lanceolate, sometimes reduced to bristles, or rarely one of them wanting ; a fifth 
scale chartaceous, at length indurated, awnless, sometimes pointed, obscurely 3-5-nerved, 
the midnerve sometimes obsolete, enclosing a faintly 2-nerved palet of similar texture and 
a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. 

Outer scales of the spikelet not winged. 
Outer scales of the spikelet manifestly winged. 

Third and fourth scales of the spikelet very small, the blade barely if at all 

manifest. 
Spikelets about 4 mm. long : panicle ovoid or oval to oblong, if the latter ex- 
ceeding 1 cm. in diameter. 2. P. CaroUniana. 
Spikelets 5-6 mm. long: panicle linear, cylindric, less than 1 cm. in diameter. 3. P. angusta. 
Third and fourth scales large, the blade broad and manifest. 4. P, Canariensis. 

1. Fhalarls arundin^cea L. Stems erect, 6-15 dm. tall : leaf-blades 1-2.5 dm. long, 



1. P. arundinacea. 



6-14 mm. wide, smooth or rough : panicle J-20 cm. long, its branches erect or ascending : 
spikelets 5-6 mm. long. 

In moist or wet soil, Nova Scotia and British Columbia to Maryland, Tennessee, Kansas, Arizona 
and California. Summer and fall. 

2. Fhalaris Caroliui^na Walt. Stems 3-12 dm. tall, erect, or sometimes decumbent 
at the base : leaf-blades 5-15 cm. long, 4-10 mm. wide, smooth or rough : panicle 1-10 
cm. long, ovoid, oval to oblong : spikelets 5-g.mm. long. 

In moist soil, South Carolina, Missouri and southern California to Florida and Texas. Summer. 

3. Fhalaris angilsta Nees. Stems erect, 8-14 dm. tall : leaf-blades rough, 2 dm. 
long or less, 5-10 mm. wide, acuminate : panicle 6-10 cm. long, cylindric, less than 1 cm. 
in diameter : spikelets about -Ijani.^ long. 

In moist soil. South Carolina and Louisiana. Spring and summer. 

4. Fhalaris Canari^nsis L. Stems 3-9 dm. tall, erect: leaf-blades 5-30 cm. long, 
4-12 mm. wide, very rough : panicle ovoid or oblong, 1.5-4 cm. long, 1-2 cm. in diam- 
eter: spikelets 6-8 mm. long. 

In waste places. Nova Scotia and Ontario to Georgia and Nebraska. Naturalized from Europe. 
Summer. Canary Grass. 

8 



lU 



rOACEAE 



50. ANTHOXANTHUM L. 



Erect aromatic annual or perennial grasses, with flat leaf-blades and terminal usually 
dense spike-like panicles. Spikelets articulated above the empty scales, 1-flowered, nar- 
row, a little compressed; crowded. Scales 5, the 2 outer persistent, empty, acute, mu- 
cronate, or short-awned, the second longer than the others, the third and fourth scales 
much sliorter, empty, narrow, keeled, awned at tlie middle or near the base, the fifth 
scale shorter tlian tlie remainder, liyaline, obtuse, awnless, enclosing a 1-nerved palet and 
a perfect flower. Stamens 2. Styles distinct. Stigmas elongated, plumose. 

1. Anthoxanthum odorktum'L. Stems 3-6 dm. tall, erect, tufted : leaf-blades 1-15 
cm. long, 2-6 mm. wide : panicle 2-6 cm. long : spikelets 8 mm. long. 

In fields and meadows throughout nearly the whole of North America. Naturalized from Europe, 
ner. SwKET Vernal (tKass.^ 



Summer 



51. SAVASTANA Schrank. 



Aromatic perennial grasses, with flat leaf-blades and contracted or open panicles. 

Spikelets 3-flowered, the terminal flower perfect, the others staminate. Scales 5 ; first and 

second nearly equal ; third and fourth a little shorter, awned or awnless, enclosing a palet 

and stamens ; fifth scale, often with a short awn, enclosing a palet and a perfect flower. 

Stamens In the staminate flowers 3, in the perfect 2. Styles distinct. Stigmas plumose. 

1. Savastana odorata (L. ) Scribn. Stems 3-6 dm. tall, simple: leaf-blades gla- 
brous ; blades on the innovations 1-3 dm, long, 2-6 mm. wide, those on the stem 1-5 cm. 
long, broad : panicle 5-10 cm. long, its branches usually spreading, naked at the base : 
spikelets 4-6 mm. long. 

In moist or wet places, Xewlbundland and New Brunswick to British Columbia, and in or near 
the mountains to North Carolina (according to Chapman), Arizona and Mexico, and Oregon. Spring 
and summer. Vaniij.a Grass. Holy Grass. 

52. ARISTIDA L. 

Tufted grasses, with narrow and often convolute or setaceous leaf-blades and contracted 
or open panicles, Avhich are sometimes nearly racemose. Spikelets 1-flowered, narrow. 
Scales 3, the outer 2 membranous, persistent, empty, narrow, keeled, awnless, usually 
longer than the third scale which is of firmer texture, narrow, rigid, strongly convolute 
about the 2-nerved palet and the perfect flower, often with a prominent callus at the base, 
3-awned from the apex, the generally spreading awns glabrous to plumose, the central awn 



2. A. Curtism. 



commonly flexuous, coiled, or bent, the lateral awns often shorter, occasionally very short 
and erect, tlie 3 awns sometimes more or less connate at the base and the column thus pro- 
duced articulated to the scale. Stamens 3. Styles distinct. Stigmas plumose. Poverty 

Grass. Wire Grass. 

A. Awns not articulated to the scale. 
Central awn coiled at the base. 

First scale usually equalling or sometimes slightly shorter than the second 

scale which is generally 7-9 mm. long. * 1. A. dichotoma. 

First scale much shorter than the second (often but little more than % as 
long) which is 10-15 mm. long. 

Lateral awns short, straight and erect, 1-2 mm, long, the central awn 

usually more than live times their length, its straight portion 5-8 
mm. long. 

Lateral awns more or less spreading, usually a little spiral at the base, 
the central awn from % again to twice their length, its straight por- 
tion from 10-15 mm. long. 
Central awn not coiled at the base. 

a. Panicle narrow, linear to oblong, the branches generally short (or the 
lower ones in No. 24 commonly elongated and ascending), usually erect 
or ascending, sometimes spreading. 

Central awn and sometimes the lateral ones also strongly reflexed, the 
bend semicircular. 
Stems simple or nearly so: spikelets many, the first scale 1-nerved, or 
sometimes with an additional faint nerve on each side. 
Spikelets less than 1 cm. long, the first scale strongly hispidulous, 
the lateral awns of the flowering scale much more slender than 
the central awn. 
Spikelets more than 1 cm. long, the first scale glabrous, the lateral 

awns about as stout as the central one. 5. A, Mohrii. 

Stems much branched : spikelets few, the first scale 5-7-nerved. 6. A. ramosissima. 

Central awn from erect to spreading with no semicircular bend at the 
base. 
♦First scale much shorter than the second, usually about % as long. 



3. A, basiramea 



4. A. simpUciflora 



rOACKAE 



115 



Spikelets crowded, 4-6 on the short panicle-branches which are 

spikelet-Vjcaring to the base or nearly so. 
Spikelets not crowded, usually 1-3, or if more numerous the branches 
of the panicle, or their divisions, with a long naked base. 
Flowering scale not twisted at the summit. 

Second scale of the spikelet 1.5 cm. long or less, usually 
equalling or slightly exceeding the flowering scale. 
Panicle simple or nearly so ; branches bearing 1 spikelet, 
or the longer sometimes 2 spikelets : stems commonly 
naked above. 

Branches appressed, the longer, exclusive of the spike- 
lets, usually 1 cm. long or less. 

Branches spreading or ascending, sometimes flexuous, 
the longer, exclusive of the spikelets, usually 1.5-3 
cm. long. 

Panicle compound ; branches bearing 2 or more spikelets : 
stems usually leafy. 
Stems stout : panicle branches straight. 
Stems slender : panicle branches filiform, fiexuous. 
Second scale of the spikelet 12-15 mm. long, the awns 
of the flowering scale commonly 8-4.5 cm. long. 
Second scale of the spikelet usually less than 1 cm. 
long, the awns of the flowering scale generally 
2 cm. long or less, rarely longer. 
Second scale of the spikelet 2 cm. long" or more, from J^ again as 
long as to nearly twice the length of the flowering scale. 
Flowering scale twisted at the summit. 

Spikelets few and scattered : flowering scale without a long 
beak, much shorter than the second scale, the awns inter- 
lacingly coiled at the base. 
Spikelets many and crowded : flowering scale with a long 
beak, equalling or exceeding the second scale, the awns 
not coiled at the base. 
** First scale a little shorter than or exceeding the second. 
Flowering scale not twisted. 

Spikelets exceeding 2 cm. long : first scale 5-7-nerved. 

Spikelets less than 1.5 cm. long : first scale 1-3-nerved. 

Sheaths glabrous, or pubescent only at the apex» 

Leaves, at least the lower ones and those on the innova- 
tions, with the base of the strongly involute blades 
densely villous. 
Leaves with the base of the flat blades at least not villous. 
First scale of the spikelet 1-nerved. 

First scale glabrous : stems single or few in a tuft. 
First scale hispidulous : stems densely tufted. 

First scale generally shorter than or equalling the 

second . 
Annual : flowering scale equalling or exceeding 
at least the body of the second scale. 
Flowering scale 5-6 mm. long, Its central awn 

usually 6-10 mm. long. 
Flowering scale 7-9 mm. long, its central awn 
exceeding 15 mm. in length. 
Perennial : flowering scale manifestly shorter 
than the second scale. 
First scale usually exceeding the second. 
First scale of the spikelet stronglv 2-3-nerv'ed. 
Sheaths, at least the lower ones, densely woolly pubescent. 
Flowering scale twisted above for the greater part of its length. 
b. Panicle diffuse and open, the branches elongated and widely spread- 
ing, with a long naked base. 
B. Awns united at the base into a spiral column which is articulated to the scale. 
Column conspicuous, 6 mm. long or more. 
Column inconspicuous, 2 mm. long or less. 



7. A.fai<ciculat(u 



8. A. Fcndlenana. 



9. A. snhuniflora. 



10. A. M'rightii. 



11. A. pxirpurea. 



12, A, micrantha, 

13. A. lonffisda. 



14. A. gyrans. 



15. A. Reverchonii. 



16. A. oligcintha. 



17. A, stricta. 



18. A, cond^iisata. 



19. A, gracilis. 

20. -(4. inter media, 

21. A. Chapmaniana, 

22. A . purpuraBcens . 

23. A.palustris, 
2i, A. lanosa, 

25. A. spidfontm. 

26. A. patula. 

'27. A, tuberculosa. 
28. A. dcsmantha. 



1. Aristida dichdtoma Michx. Stems densely tufted, slender, 2-6 dm. tall, finally 
branching: leaf -blades erect, 2-9 cm. long, 1.5 mm. wide or less, sparingly pilose above 
toward the base : panicle 3.5-7 cm. long, the branches short or erect : spikelets 7-9 mm. 
long, the 2 outer scales about equal in length, or the first a little the shorter, usually awn- 
pointed, the flowering scale 5-7 mm. lon^, the lateral awns very short, erect, the centnil 
awn spreading, spiral at the base, the straight portion 2-5 mm. long, rarely longer. 

In dry sandy soil, Maine to Ontario, Missouri and the Indian Territory, Florida and Texas. 
mer and fall. Poverty Grass. 

2. Aristida Curtissil (A. Gray) Nash. Stems tufted, 2-5 dm. tall, branching : leaf- 
blades 4-16 cm. long, 1-2 mm. wide, sometimes sparsely pilose above near the base : pani- 
cle 5-9 cm. long, the branches erect: spikelets generally 10-12 mm. long, rarely longer, 

first scale much shorter than the second which usually about equal 



Sum- 



rarely somewhat exceeding it, the flowering scale 7-11 mm. long, the lateral awns very 
short, 1-2 mm. long, straight and erect, usually less tlian ^ ' 
which has the straight portion 5-8 mm. long. 



long as the central awn 



In drj' soil. Missouri and Kansas to the Indian Territory : also in Virginia. Fall. 



116 



POACEAE 



3. Aristida baslramea Engelm. Stems tufted, rather slender, 2-6 dm. tall, branch- 
ing: leaf-blades 3-15 cm. long, 1.5 mm. wide or less, sometimes sparsely pilose above at 
the base : panicle 3-9 cm. long, the branches erect : spikelets 10-15 mm. long, the first 
scale much shorter than the second, the flowering scale 7-11 mm. long, considerably shorter 
than the second, the lateral awns more or less spreading, usually a little spiral at the base, 
J-§ as long as the central awn which is strongly spiral at the base and with the straight 
portion 10-18 mm. long. 

In drj^ fields, Manitoba to Illinois, Nebraska and the Indian Territory. Summer and fall. 

4. Aristida simpliciflora Chapm. Stems tufted, 4-6 dm. tall, slender, simple or 
sparingly branched : leaf-blades 3.5-15 cm. long, 1-1.5 mm. wdde, flat: panicle 1-2 dm. 
long, its branches short and appressed : spikelets 8-9 mm. long, crowded, the 2 outer scales 
1 -nerved, about equal or the first a little the shorter, the flowering scale 5-6 mm. long, the 
central awn 12-15 mm. long, strongly reflexed, the lateral awns ascending, about ^ as 
long and much more slender than the central awn. 

In low pine woods, Florida. Fall. 

5. Aristida Mobrii Nash. Stems 5-7 dm. tall, simple : leaf -blades 5-12 cm. long, 
1-1.5 mm. wide, those on the innovations hirsute above : panicles 1.5-3 dm. long, simple : 
spikelets 10-12 mm. long, on very short pedicels, appressed, scattered, the 2 outer scales 
1-nerved, the first equalling or often a little exceeding the second, the flowering scale 8-9 
mm. long, the awns of equal thickness, all strongly reflexed, the central one 15-18 mm. 
long, the lateral ones a little shorter. 

On dry sandy pine ridges, Alabama. Fall. 

6. Aristida ramosissima Engelm. Stems tufted, 2-4 dm. tall, slender, branched: 
leaf-blades 4-15 cm. long, 1-1.5 mm. wide, flat: panicle 6-10 cm. long, simple, the 
branches very short and bearing a single usually ascending spikelet : spikelets 1,6-2.2 cm. 
long, the 2 outer scales usually awned, the first scale 5-7-nerved, shorter than the 3-nerved 
second, the flowering scale 15-18 mm. long, the central awn strongly reflexed, 2-3 cm. 
long, the lateral a^ns rigid, erect, 1-2 mm. long. 

In dry ground, Illinois and Missouri to the Indian Territory. Late summer and fall. 

7. Aristida fascicul^ta Torr. Stems tufted, 5-8 dm, tall, branched : leaf-blades 6 -12 
cm. long, 1-2 mm. wide : panicle 7-20 cm. long, its branches short, in fascicles of 2-4, 
erect or nearly so : spikelets 9-10 mm. long, crowded, the 2 outer scales 1-nerved, the first 
one i-| as long as the second, the flowering scale 8-12 mm. long, hispidulous on the keel, 
the callus densely pilose, the awns ascending, the central one 10-17 mm. long, the lateral 
awns f-i as long. 

In dry soil, Kansas to California, Texas, Mexico and New Mexico. Fall. 

8. Aristida Fendlerlkna Steud. Stems densely tufted, 1.5-2.5 dm. tall, erect, rigid, 
simple : leaf-sheaths smooth, confined to the base of the stem, a tuft of hairs on each side 
at the apex ; blades involute, at least when dry, often curved, 0.5 mm. in diameter, those 
on the stem usually 2, 1.5-5 cm. long, the basal longer : panicle 7-10 cm. long, strict, its 
branches short and appressed and usually bearing but a single spikelet, rarely exceeding 
1.5 cm. long, or sometimes the lower ones with 2 spikelets : spikelets 12-15 mm. long, the 
2 outer scales 1-nerved, the first scale about ^ as long as the second, the flowering scale 
9-12 mm. long, equalling or a little shorter than the second scale, the awns ascending, the 
central one 2-3.5 cm. long, the lateral ones a little shorter. 

In dry sandy soil, South Dakota to Utah, Texas and New Mexico. Summer and fall. 

9. Aristida subuniflora Nash. Stems densely tufted, 2.5-3.5 dm. tall, erect, 
simple : leaf-sheaths usually confined to the base of the stem ; blades involute, at least 
when dry, usually straight, sometimes curved, those on the stem usually 2, 2-4.5 cm. long, 
the basal longer : panicle 6-13 cm. long, its branches more or less spreading, the larger 
ones 2-3 cpi. long, bearing 1 or 2 spikelets : spikelets 1.5-2 cm. long, the 2 outer scales 
1-nerved, the first about J as long as the second, the flowering scale 13-15 mm. long, 
usually a little shorter than the second scale, the awns ascending, the central one 3-5 cm. 
long, the lateral awns a little shorter. 

In dr>' sandy soil, central Texas to New Mexico. Spring and summer. 

10._ Aristida Wrightii Nash. Stems tufted, 3.5-5 dm. tall, simple, leafy: leaf- 
blades involute, at least when dry, those on the stem usually 3 or 4, 3-20 cm. long, often 
curved, as are the commonly longer basal ones: panicle 1-2 dm. long, its branches more 
or less spreading, the longer usually bearing 2-4 spikelets : spikelets 12-15 mm. long, 
the 2 outer scales 1-nerved, the first scale about i as long as the second, the flowering scale 
10-12 mm. long, usually a little shorter than the second scale, the awns ascending, the 
central one 2.5-3 cm. long, the lateral awns a little shorter. 

In dry sandy soil, Kansas to Texas and New Mexico. Summer and fall. 



POACEAE 



117 



11. Aristida purpurea Nutt. Stems tufted, 2-4 dm. tall, slender, simple, leafy : 
leaf-blades involute, at least when dry, often curved, those on the stem 2-5, 4-12 cm. 
long : panicle 1-2 dm. long, its branches spreading or ascending, tiliform, flexuous, often 
with a long naked base : spikelets 12-15 mm. long, the 2 outer scales 1-nerved, fre(iuently 
awned, the first about J as long as the second, the flowering scale about 1 cm. long, a little 
shorter than the second scale, the awns ascending, the central one about 3-5 cm. long, 
the lateral awns a little shorter. 

In dry sandy soil, Arkansas and Louisiana, to New Mexico. Spring and summer. 

12. Aristida micrdntha ( Vasey) Nash. Stems tufted, 2-4 dm. tall, slender, simple : 
leaf-blades 4-15 cm. long, involute, at least when dry : panicle 8-12 cm. long, its branches 
filiform, flexuous, spreading or ascending: spikelets 2-4 on the longer branches, the 2 
outer scales l-nerved, the second one 8-10 mm. long, the flowering scale 6-8 mm. long, the 
awns ascending or nearly erect, the central awn 1.5-2 cm. long, rarely longer, the lateral 
awns a little shorter. 

In dry soil, Texas. Summer. 

13. Aristida longis^ta Steud. Stems tufted, 2-4 dm. tall, simple : leaf-blades 3-10 
cm. long, involute, at least when dry : panicle 1-2 dm. long, its branches usually ascend- 
ing, bearing generally 1 spikelet, or in the longer branches sometimes 2 spikelets : spike- 
lets 2-2.5 cm. long, the 2 outer scales 1-nerved, the firet one about J as long as the second, 
the flowering scale 12-16 mm. long, occasionally a little shorter, from a little over I f as 
long as the second scale, the awns ascending, the central one 6-11 cm, long, the lateral ones 
equalling it or a little shorter. 

In dry sandy soil, Montana and Washington to Nebraska, Texas and Mexico. Summer and fall. 

14. Aristida gyrans Chapm. Stems 3-4 dm. tall, slender, simple : leaf-blades 
6-12 cm. long, involute, about 0.5 mm. in diameter : panicle about 12 cm. long, slender, 
its few branches short and appressed : spikelets 10-11 mm. long, the 2 outer scales 1-nerved, 
the first one shorter than the second, the flowering scale about 6 mm. long, including the 
1.5 mm. long callus, the apex a little twisted, the awns ascending, loosely twisted together 
at the base, the central awn about 12 mm. long, the lateral ones a little shorter. 

In sand, Keys of Caximbas Bay, southern Florida ; also in Cuba. Summer and fall. 

15. Aristida Reverchonii Vasey. Stems tufted, 2-4 dm. tall, simple : leaf-blades 
2-12 cm. long, involute, about 0.5 mm. in diameter: panicle 1-1.5 dm. long, its branches 
usually short and appressed, rarely long and somewhat spreading : spikelets on short pedi- 
cels, the 2 outer scales 1-nerved, the first one much shorter than the second which is 8-10 
mm. long, the flowering scale 9-11 mm. long, usually hispidulous, with a long slender 
more or less twisted summit, a little exceeding the second scale, the awns ascending, the 
central one 1.5-2.5 cm, long, the lateral ones a little shorter. 

In dry soil, the Indian Territory and Texas. Spring and summer. 

16. Aristida oligdntha Michx. Stems tufted, 2-6 dm. tall, branching : leaf-sheaths 
shorter than the internodes, smooth and glabrous ; blades 0.5-2 dm. long, 1-2 mm. wide : 
panicle 1-2 dm. long, simple, its branches very short and bearing a single spreading spike- 
let : spikelets 2-3 cm. long, the 2 outer scales usually awned, the first 5-7 -nerved, from a 
little shorter than the second to a little exceeding it, 1.5-2 cm. long, the awns ascending, 
the central one 3.5-7 cm. long, the lateral ones a little shorter. 

In dry usually sterile soil, Xew Jersey to Nebraska, Mississippi and Texas. Summer and fall. 

17. Aristida stricta Michx, Stems densely tufted. 5-10 dm. tall, simple : leaf- 
sheaths, the lower ones and especially those on the innovations, villous at the apex ; blades 
involute, even when fresh, 0.5-3 dm. long, about 0.7 mm. in diameter, the lower ones and 
those on the innovations densely villous at the base : panicle 1-3 dm. long, the short ap- 
pressed branches in alternate fascicles of 2 or 3 : spikelets 10-11 mm. long, the 2 outer 
scales 1-nerved, usually awn-pointed, the first shorter than the second, the flowering scale 
7-9 mm. long, glabrous or sparingly hispidulous toward the summit, the awns more or less 
spreading, the central one 11-17 mm. long, the lateral ones from | to nearly as long. 

In dry sandy soil. Virginia (according to S. Watson) to Florida. Spring to fall. 

18. Aristida condens^ta Chapm. Stems single or few in a cluster, 6-10 dm. tall, 
simple : leaf -sheaths confined to the lower part of the stem, overlapping, glabrous or spar- 
ingly pubescent ; blades 2-3 dm. long, flat when fresh, 2-3 mm. wide at the base from 
which they gradually taper to a long slender acumination : panicles 2-5.5 dm. long, usually 
densely spikelet-bearing, its branches erect or nearly so, the longer from 3-13 dm. long, 
the spikelets crowded and overlapping: spikelets 8.5-10 mm. long, the 2 outer scales 
1-nerved, glabrous, the first equalling or very little shorter than the second, the flowering 
scale about 7 mm. long including the 1 mm. long and densely pilose callus, glabrous, the 
awns spreading, the central one 10-14 mm. long, the lateral ones from | as long as to 
nearly equalling it. [A, Combsii Scribn. & Ball.] 

In drj' sandy soil, Florida. Fall. 



118 



roACEAE 



19. Aristida grdcills Ell. Stems densely tufted, 1.5-6 dm. tall, slender, finallj 
more or less branched : leaf-sheaths equalling or shorter than the internodes, glabrous, 
or the lower ones sparingly pubescent; blades 3-12 cm. long, 1 mm. wide or less, erect, 
flat : panicle 5-15 cm. long, its short branches appressed : spikelets 5-7 mm. long, the 
2 outer scales l-nerved, usually awn-pointed, the first equalling or a little shorter than the 
second, sparingly hispidulous, the flowering scale 5-6 mm. long, frequently barred or 
spotted with black, more or less hispidulous, especially on the keel, the central awn 
spreading, 6-10 mm. long, rarely longer, the lateral awns erect, 1-3 mm. long, occasion- 
ally longer. 

In dry soil, Vermont to Illinois, Kansas, Florida and Texas. Summer and fall. 

20. Aristida intermedia Scribn. & Ball, Stems slender, finally branching, 3-8 
dm. tall : leaf -sheaths glabrous or sparsely hirsute ; blades 5-15 cm. long, 2 mm, wide or 
less, erect, involute : panicle 2-4 dm. long, slender, its branches appressed : spikelets 8-10 
mm. long, the empty scales manifestly awned, about equal, the flowering scale strongly his- 
pidulous above the middle, equalling or exceeding the empty scales, the awns spreading, 
the middle one 15-25 mm. long, the lateral ones snorter. 

In sandy soil, Iowa to Mississippi and Texas. Summer and fall. 

21. Aristida Chapmani^na Nash. Stems densely tufted, 7-10 dm. tall, finally more 
orlessbranclied : leaf -blades 1-2 dm. long, 1.5-2.5 mm. broad, flat, long-acuminate : panicle 
2-4 dm, long, the branches short and appressed : spikelets 6-8 mm. long, rather crowded 
on the branches, the 2 outer scales l-nerved, or the first rarely with faint lateral nerves, 
the first one shorter than the second, usually strongly hispidulous, the flowering scale about 
5 mm. long, glabrous or sparingly hispidulous on the upper part of the keel, the central awn 
widely spreading, at right angles to the scale, 1.8-2.5 cm. long, the lateral awns erect, 
usually a little more than J as long as the central awn, rarely shorter. 



In dry sandy soil, North Carolina to Florida and Mississippi. Fall. 

22. Aristida purpnr^scens Poir. Stems tufted, 3-8 dm. tall, usually simple, or 
occasionally branched: leaf-sheaths smooth and glabrous, or the lower ones sometimes 

fmbescent ; blades 0.5-2 dm, long, 1-2 mm, wide, flat, long-acuminate : panicle 1.5-3 dm, 
ong, its branches appressed and usually short : spikelets 9-12 mm, long, rarely a little 
smaller, usually crowded, the 2 outer scales l-nerved, sometimes awn-pointed, the first 
one usually exceeding the second, occasionally equalling it, hispidulous, the flower- 
ing scale 6-8 mm. long, glabrous or sparingly hispidulous, the awns more or less spreading, 
especially the centnil one which is 1.5-2.5 cm. long, the lateral awns from t Jis long to 
nearly equalling it. 

In dry soil, Massachusetts to Minnesota, Florida and Texas. Fall. 

23. Aristida paliistris (Chapm.) Vasey. Stems densely tufted, 8-12 dm, tall, firm 
and hard at the base : leaf-blades 2-4 dm. long, 2-3 mm. wide : panicle 2-5 dm. long, its 
branches closely appressed, the longer 5-7 cm, long : spikelets 10-12 mm. long, the first 
scale prominently 2-3-nerved, strongly hispidulous, from a little shorter than to slightly 
exceeding the second, the flowering scale 8-9 mm. long, smooth and glabrous, the callus 
fully 1 mm. long, sparsely pilose, the central awn widely spreading, 1.5-3 cm. long, the 
lateral awns erect or nearly so, from f as long as to nearly equalling it. 

In swamps and wet places, Florida to Louisiana. Late summer and fall. 

24- Aristida lanosa MuhL Stems 8-14 dm. tall, simple, rather stout: leaf-sheaths 
confined to the lower part of the stem, densely woolly pubescent ; blades 3-5 dm. long, 2-7 
mm, wide, flat : panicle 4-6 dm. long, its axis villous at the nodes, its lower branches dis- 
tant, ascending, 8-12 cm. long : spikelets 12-17 mm. long, the 2 outer scales l-nerved, the 
first much exceeding the second, the flowering scale 8-10 mm. long, the central awn widely 
spreading, 1.5-2.5 cm. long, the lateral awns erect or ascending, about i as long. 

In dry thickets, Delaware to Florida, and Texas. Fall. 

25. Aristida spiciformis Ell. Stems tufted, 4-10 dm, tall, simple : leaf-sheaths^ 
overlapping on the lower part of the stem ; blades 1-3 dm. long, flat, or involute when dry, 
3-5 mm. wide : panicle 12-20 cm. long, oblong, very dense : spikelets densely crowded, 
the 2 outer scales l-nerved, the first scale about i as long as the second which i 
1 cm, long, the former with an awn longer than "its body, the latter bearing an awn of 
about equal length, the flowering scale, exclusive of the awns and including the 2 mm. long 
callus, about 6 mni. long, the awns united below into a twisted flexuous column 1.5-2.5 cm. 
long, the free portion of the awns spreading or ascending, the central a^vn 2.5-3.5 cm. long 
the lateral ones a little shorter. 

In moist or flat pine lands, South Carolina to Florida. Summer and fall. 

26. Aristida pdtula Chapm. Stems tufted, 1-1.5 m. tall, simple, the leaves confined 
to the lower part of the stem : leaf-sheaths overlapping, smooth, usually with a pubescent 



is about 



9 



POACEAE 



119 



ring at tlie summit ; blades 2-6 dm. long, 3-5 mm. wide, flat, glabrous, smooth, even on 
the margins : panicle 4-6 dm. long, its branches widely spreading, rough, divided, the 
larger ones 2-3 dm. long : spikelets on short pedicels, the 2 outer scales 1-nerved, more or 
less awned, the first one 11-14 mm. long, usually exceeding the second, rarely equalling 
or a little shorter than it, the flowering scale 1-1.5 cm. long, smooth and glabrous, the awns 
erect or nearly so, the central one 2-3 cm. long, the lateral ones j-f as long. 
In dry sandy soil, peninsular Florida. Summer and fall. 

27. Aristida tuberculosa Xutt. Stems tufted, 2-5 dm. tall, branched : leaf-sheaths 
shorter than the Internodes, the lower ones pubescent ; blades 8-20 cm. long, 1.5-2.5 mm. 
wide, flat : panicle 1-2 dm, long, its branches erect or ascending, the larger ones 6-10 cnu 
long : spikelets on short pedicels, the 2 outer scales 1-nerved, awn-pointed, the body of the 
first shorter than that of the second which, exclusive of the awn, is about 2 cm. long, the 
flowering scale, exclusive of the awns and including the 2-3 mm. long callus, 12-15 mm. 
long, the awns united at the base into a spiral column 6-20 mm. long which is articulated to 
the scale, the free portion finally reflexed and sometimes coiled at the base, the central awa 
3.5-5 cm. long, the lateral ones a little shorter. 

In sandy soil, especially along sea beaches, Massachusetts to Georgia; also in the interior iii 
Minnesota, Wisconsin and lUinois. Summer and fall. 

28. Aristida desmdntha Trin. & Rupr. Stems 4-8 dm. tall, branching: lower leaf- 
sheaths pubescent ; blades 6-30 cm. long, 1.5-2 mm. wide, flat, or involute when dry : 
panicle 1.5-2 dm. long, its branches erect or nearly so, the lower ones 6-8 cm. long : spike- 
lets on short pedicels, the 2 outer scales awned, 1-nerved, the first one sometimes with 2 
or 3 lateral nerves on each side, the first usually 'equalling or shorter than the second 
which is 12-14 mm. long, exclusive of the awn, rarely exceeding it, the flowering scale, 
exclusive of the awms, 8-10 mm. long, the awns united at the base into a usually spiral 
column 2 mm. long or less which is articulated to the scale, the free portion finally reflexed 
and usually coiled at the base, the central awn 2.5-3 cm. long, the lateml ones a little 
shorter. 

In dry soil, the Indian Territory and Texas. Summer. 

53. ORTACHNE Nees. 

Tall usually slender grasses, with flat or involute leaf-blades and terminal panicles. 
Spikelets 1 -flowered : empty scales narrow, acuminate, usually awn -pointed : flowering scale 
narrow, merging into the single terminal awn. Stamens 3. Styles distinct. Stigmas 
plumose. 

1. Ortachne Florid^na (Chapm. ) Nash. Stems 6-10 dm. tall, simple: leaf-blades 
2-3 dm. long, involute, at least when dry, about 1 mm. in diameter : panicle 2-3 dm. long, 
its branches ascending, the larger ones 8-14 cm. long : spikelets 9-11 mm. long, the 2 outer 
scales 1-3-nerved, the first from a little shorter than to somewhat exceeding the second, 
the floAvering scale 1.5-2 cm. long, compressed, curved at the summit, gradually tapering 
into the single awn which is 14-18 mm. long. [^Aristida Floridana (Chapm.) VaSey.] 

In dry places, Key West, Florida. Spring to fall. 

54. STIPA L. 

Tufted grasses, Avith convolute or flat leaf-blades and terminal contracted or open, often 
slender, panicles. Spikelets narrow, 1-flow^ered, usually few and large, or sometimes 
smaller and numerous. Scales 3, the 2 outer empty, persistent, narrow, keeled, acute, 
rarely awned, the third scale tightly convolute about the 2-nerved or 2-keeled palet and 
the perfect flower, rigid, narrow, the apex usually attenuated into a more or less geniculate 
awn (or rarely 2-toothed or shortly 2-cleft, with the awn strict and arising between the 
teeth) which is often spiral or twisted at the base, and generally deciduous at the articula- 
tion to the scale, rarely not articulated and persistent. Stamens 3, or rarely fewer, the 
anthers very often barbellate at the apex. Styles short, distinct. Stigmas plumose. 

Flowering scale abruptly contracted above into a smooth cylindric appendage over 

1 mm. long and hairy at the apex. 1. S, leucotricha. 

Flowering scale not thus appendaged : 

About 1 cm. long : empty scales 8-12 mm. long. 2. S. avenacea. 

Exceeding 1.5 cm. in length : empty scales 1.5 cm. long or more. 3. S. avenaceoides, 

1. Stlpa leucotricha Trin. Stems tufted, 3-5 dm. tall, erect : leaf-sheaths glabrous, 
or sparingly pubescent, the upper one often enclosing the base of the panicle ; blades rather 
sparingly pubescent with short spreading hairs, 2 dm. long or less, 2-3 mm. wide : panicle 
1-1.5 dm. long, its branches erect: spikelets 15-18 mm. long, exclusive of the awn ; 



120 



POACEAE 



empty scales green, acuuiinate ; flowering scale about 1 cm. long, usually strongly papil- 
lose-ronghened, the callus about 4 mm. long and strongly pubescent with Avliite appressed 
hairs the awn 6-8 cm. long, spiral and very pubescent at the base, usually twice bent. 

In dry soil, Texas. Spring and summer. 

2. Stipa avenacea L. Stems 3-8 dm. tall : leaf-blades involute-filiform, the basal 
J-J as long as the stem, those on the stem 7-13 cm. long : panicle 1-2 dm. long, loose, its 
branches lax and finally spreading : empty scales of the spikelet 8-12 mm. long ; flowering 
Bcale shorter, black, hairy at the base, and with a ring of short hairs at the top, the awn 
4-7 cm. long, bent, loosely spiral below. 

In dry woods, Rhode Island to Florida, mostly near the coast ; also in western Ontario and AVis- 
consin. Black Oat Grass. 

3. Stipa avenaceoides Xash. Stems 6-12 dm. tall, tufted, erect, slender : leaf- 
sheaths glabrous ; blades involute-setaceous, glabrous, the basal ones about 3 dm. long, 
those on the stem 2.5-12 cm. long : panicle simple, 1-2.5 dm. long, finally long-exserted, 
its brandies 2.5-8 cm. long: spikelets few; empty scales purple at the base, acuminate, 
15-22 mm. long ; flowering scale glabrous, excepting the hairy apex, 1.5-2 cm. long, in- 
cluding the callus which is 6-8 mm. long and covered with appressed brown hairs, the awn 
7-10 cm. long, pubescent below, spiral at the base, twice bent. 

In dry sandy soil, peninsular Florida. Spring and summer. 

55. MUHLENBERGIA Schreb. 

Perennial or rarely annual grasses, various in habit, with flat or often involute leaf- 
blades, and terminal contracted or open panicles, which are often slender, densely thyrsoid, 
or almost spike-like, or diffuse with long capillary branches. Spikelets 1 -flowered, small. 
Scales 3 (or rarely 4), the outer 2 empty, persistent, membranous or hyaline, from minute 
to almost equalling the third scale, keeled, acute, mucronate or rarely short-awned, the 
second occasionally 3-toothed, the third scale somewhat rigid, convolute about the 2-keeled 
hyaline palet and the perfect flower, at the apex entire or rarely 2-toothed, obtuse, acute, 
mucronate to long-awned, the awn very often capillary, a fourth awned scale very rarely 
present. Stamens usually 3, rarely fewer. Styles distinct. Stigmas plumose. 

Panicle contracted, its branches erect or nearly so : spikelets on short pedicels. 
Empty scales at least y^ as long as the spikelet. 

Flowering scale not awned, but sometimes awn-pointed. 

Empty scales not awned, about % as long as the flowering scale, acute, 1. M. soholifera. 



2. 3L MexicaTia, 

3. M, racemosa. 



Empty scales long-acuminate, awn-pointed or awned. 

Empty scales about as long as the flowering scale, sharp- pointed, about 
3 mm. long. 

Empty scales exceeding the flowering scale, usually twice as long, awned, 

about 5 mm. Ion; 
Flowering scale long-awned, the awn usually twice as long as the scale. 
, Empty scales about equalling the flowering scale. 4. M. sylvatica. 

Empty scales %-% as long as the flowering scale. 5. M. tenuiflora, 

Empty^cales minute, the first one often wanting. 6. M, diffusa. 

Panicle open, its tiliform branches spreading or ascending: spikelets on very long 
capillary pedicels. 
Stems erect, simple. 

Empty scales awnless, or awn-pointed : 

Awn of the flowering scale very short, rarely nearly equalling it in length. 7. 3f. trichopodes. 
Awn of the flowering scale very long, often several times its length. 8. M, capillaris. 

Empty scales long-awned, the awns usually many times as long as the scale. 9. M. JUipes, 
Stems much branched and prostrate. 10. M. Porteri, 

1. Muhlenbergia aobolifera (Mulil. ) Trin. Stems 3-9 dm. tall, erect, slender, 
simple, or sparingly branched above : leaf -blades rough, those on the stem 1-1.5 dm. long, 
2-(? mm. wide, those on the branches 2-8 cm. long and about 2 mm. wide : panicle 7-15 
cm. long, slender : empty scales about 1 mm. long, the flowering one obtuse, scabrous, 
the midnerve usually excurrent as a short tip. 

In rocky woods, New Hampshire and Massachusetts to Minnesota, Virginia, Tennessee and the 
Indian Territorj*. Summer and fall. 

2. Muhlenbergia Mexlckna (L. ) Trin. Stems 6-12 dm. long, erect, or often pros- 
trate, much branched : leaf-blades rough, those on the stem 1-1.5 dm. long, 2-6 mm. 
wide, the branch blades smaller: panicle 5-15 cm. long, contracted : spikelets 2.5-3 mm. 
long, the outer scales somewhat unequal, acuminate or short-awned, rough, especially on 
the keel, the third scale acuminate, rough. 

In swamps and borders of fields, New Brunswick to western Ontario, North Carolina, Tennessee, 
Nebraska and the Indian Territory. Summer and fall. 

3. Muhlenbergia racemosa (Michx. ) B.S.P. Stems 3-9 dm. tall, erect, usually 
much branched : leaf-blades 5-13 cm. long, 2-6 mm. Avide, rough: panicle 5-12 cm. long, 



-^ 



puacp:ae 



121 



N 



usually dense and interrupted : spikelets much crowded, the empty scales acuminate, 4-6 
mm. long, including the awn, the flowering scale ^-f as long, acuminate, the strongly 
scabrous midnerve excurrent as a short point. \_M. glomerata Trin.] 

In wet places, Newfoundland to British Columbia, New Jersey, North Carolina, Missouri, and 
New Mexico. Summer and fall. 

4. Muhlenbergia sylvdtica Torr. Stems 3-9 dm. tall, erect, branched : leaf-blades 
5-18 cm. long, 2-6 nun. wide, rough : panicle 7-18 cm. long, somewhat lax : empty scales 
of the spikelet 2.5-3 mm. long, awn-pointed, rough, the third scale equalling or somewhat 
exceeding the outer ones, very rough, attenuate into a slender awn 2-4 times its length. 

In moist woods and along streams, New Brunswick to Ontario, Minnesota, North Carolina, Ten- 
nessee, Nebraska and the Indian Territory. Summer and fail. 

5. Muhlenbergia tenuiflora (Willd. ) B.S.P. Stems 6-9 dm. tall, erect, slender, 
simple or sparingly branched : leaf-blades 6-18 cm. long, 2-8 mm. wide, narrowed toward 
the base, acuminate, rough : panicle 1-2.5 dm. long, slender: empty scales of the spikelet 
unequal, J-| the length of the flowering scale, awn-pointed, rough, the flowering one 
2.5-3 mm. long, rough, bearing an awn 2-4 times its length, [il/. WUdenovU Trin.] 

In rocky woods, Massachusetts to southern Ontaria, Minnesota, Alabama and Texas. Summer 
and fall. 

6. Muhlenbergia diffusa Willd. Stems 3-9 dm. long, decumbent, or often prostrate 
or creeping and ascending, very slender, diffusely branched : leaf-blades 4-9 cm. long, 1-4 
mm. wide, rough : panicle 5-20 cm. long, slender, somewhat lax : empty scales of the 
spikelet minute, the lower one often wanting, the flowering scale, exclusive of the awn, 
about 2 mm. long, very rough, especially on the nervesi, the aAvn 1-4 mm. long. 

On dry hills and in woods, Maine and southern Ontario to Minnesota, Florida, Kansas and 
Texas. Summer and fall. 

7. Muhlenbergia trichopodes ( Ell. ) Cliapm. Stems tufted, wiry, 7-10 dm. tall : 
leaf-blades long and narrow, stifl', often involute when dry : panicle 2-4 dm. long, its 
branches erect : spikelets, exclusive of the awn, 3.5-4.5 mm. long, the empty scales 
acuminate, shorter than the flowering scale, sometimes awn-pointed, the flowering one 
bearing a short awn 2 mm. long or less. 

In pine lands, North Carolina to Florida and Texas. Summer and fall. 

8. Muhleabergia capiilaris (Lam. ) Trin, Stems erect, wiry, tufted, 5-12 dm. tall : 

leaf-blades long and narrow, often involute when dry, 1-3 ^m. wide: panicle 1.5-4 dm. 

long, its branches spreading or ascending : spikelets, exclusive of the awn, 3.5-4 mm. long, 

lanceolate, acuminate, the empty scales usually h as long as the spikelet or less, commonly 

bearing a short awn, the flowering scale bearing an awn longer than its body, sometimes 2 

cm. long. [7J/. caespitosa Chapm,] 

In dry soil and pine lands, Massachusetts, New Jersey and Missouri to Florida, the Indian Terri- 
tory and Texas. Also in Cuba. Fall. 

9. Muhlenbergia filipes M. A. Curtis. Stems tufted, erect, wiry, 5-10 dm. tall : 
leaf-blades long and narrow, involute, at least when dry, 1-2 mm. wide : panicle 2-3 dm. 
long, often included at the base, its long branches spreading or ascending : spikelets, ex- 
clusive of the awns, 4-5 mm. long, lanceolate, acuminate, the empty scales i as long as the 
spikelet or less, bearing a long awn, that on the second scale, and also often that on the first, 
frefjuently much exceeding the spikelet. 

In sands on the seashore and in pine lands, North Carolina to Florida and Mississippi. Fall. 

10. Muhlenbergia Porteri Scribn. Stems 2-6 dm. long, much branched and pros- 
trate : leaf-blades 3-6 cm. long, 1-2 mm. wide, flat, acuminate, linear : panicles 8-10 cm, 
long, the branches widely spreading, rather stiflT: spikelets, exclusive of the awn, 3-4 mm. 
long, the empty scales acuminate, shorter than the spikelet, the flowering one bearing an 
awn 5-10 mm. long. 

On hills and plains, central Texas to southern Oalifornia. Summer and fall. 

56. BRACHYELYTRUM Beau v. 

Tall perennial grasses, with rather broad flat leaf-blades and a terminal narrow panicle, 
its branches few, erect and filiform. Spikelets 1-flowered, narrow, the rachilla produced 
beyond the flower into a long glabrous stipe which sometimes bears a small scale at its 
apex. vScales 3 (or rarely 4), the 2 outer empty, persistent, very small, the first minute, 
sometimes almost wanting, the third scale elongated, rather rigid, acuminate into a long 
*»rAot nvin ni^/i ^.^^i^c-Jiirr n t:rtmowTint «h*^rt florsjillv jmloftte 2-nerved Dale t of similar texture 



Stamens 2. Styles short, distinct. Stigmas elongated, plumose. 



prolongat 






122 



POACEAE 



1. Brachyelytrum er6ctum (Schreb.) Beauv. Stems 3-9 dm. tall, pubescent at and 
near the nodes : leaf-sheaths villous, especially at the throat ; blades 5-13 cm. long, 6-18 
mm. wide, rough : panicle 5-15 cm. long, slender, its branches erect or appressed : empty 
scales of the spikelet unequal, the upper one less than J as long as the flowering scale, the 
lower minute or wanting, the flowering saile, exclusive of the aAvn, 9-12 mm. long, rough, 
the awn erect, 2-2.5 cm. long. [f?. aristatum K. & S.] 



wood 



Summer, 



57. PHLEUM L. 



Annual or perennial gnu^ses, with flat leaf -blades and terminal, often long-pedunculate, 
dense spike-like panicles, which are from elongated, narrow and cylindric, to short, oblong 
or nearly ovoid. Spikelets crowded, 1 -flowered, compressed. Scales 3, tlie 2 outer empty, 
persistent, membranous, compressed-keeled, obliquely truncate at the summit, awned, the 
third scale much shorter, hyaline, truncate and denticulate at the apex, enclosing a nar- 
rower palet of similar texture and a perfect flower. Stamens 3. Styles distinct, rather 
long. Stigmas plumose. 

1. Phleum prat6nse L. Stems 3-12 dm. tall, erect, simple : leaf-blades 7-23 cm. 
long, 4-6 mm. wide, smooth or rough : spike usually elongated, cylindric, 3-18 cm. long, 
5-8 mm. in diameter: empty scales of the spikelet, exclusive of the awn, 2.5 mm. long, 
ciliate on the keel, the awn less than J their length. 

In fields and meadows nearly throughout North America. Widely cultivated. Also in Europe 
and Asia. Hummer. Timothy. 

58. ALOPECIJRUS L. 

Annual or perennial grasses, erect, or decuuibeut at the base, with flat and lax or 
rather rigid or convolute leaf-blades, and dense terminal spike-like cylindric panicles. 
Spikelets articulated below the empty scales, readily deciduous, 1-flowered, compressed, 
crowded. Scales 3, the 2 outer empty, acute, sometimes short-aw^ned, usually more or less 
united at the base, compressed-keeled, the keel ciliolate or somewhat winged, the third 
scale broad, hyaline, obtuse, bearing a short awn or point on the back, the margins some- 
times united into a short tube at the base, enclosing a perfect flower and sometimes also a 
hyaline keeled palet. Stamens 3. Styles distinct, or rarely more or less united at the 
base. Stigmas elongated, somewhat plumose Avith short hairs. Foxtait.. 

Empty scales of the spikelet united for ^ their length, glabrous to hispid on the 

keel. 1. A. agrestts. 

Empty scales of the spikelet united for % their length or less, long-ciliate on the 

keel. 2. A. geniculatus. 

1. Alopecurus agr^stis L. Stems 3-6 dm. tall, erect, simple : leaf-blades 4-18 cm. 
long, 2-6 mm. wide, rough, especially above : spike 4-10 cm. long, 4-8 mm. in diameter : 
empty scales of the spikelet narrowly winged, 4-5 mm, long, the flowering scale equalling 
or slightly exceeding the empty ones, smooth and glabrous, the awn inserted near the 
base and about tAvice its length, bent. 

In waste places and on ballast, soutliern New York, New Jersey, and Mississippi. Summer. 

2. Alopecurus geniculktus L. Stems 1.5-4.5 dm. tiill, erect, or sometimes decumbent 
at the base : leaf-blades 2-15 cm. long, 1-4 mm. wide, rough, especially above : spike 2-8 
cm. long, 4-8 mm. in diameter: empty scales of the spikelet 2-2.5 mm. long, obtuse or 
subacute, glabrous, excepting the lateral nerves and strongly ciliate keel, the flowering 
scale somewhat shorter, obtuse, the awn inserted at or below the middle, equalling or ex- 
ceeding it. 

In wet soil, Newfoundland to British Columbia, Florida, Tennessee, Arizona, and California. 
Also in Europe and Asia. Summer and fall. 

59. SPOROBOLUS E. Br. 

Perennial or rarely annual grasses, varying much in habit, with flat or convolute leaf- 
blades and terminal panicles, which are contracted, sometimes cylindric and spikg-like, 
often elongated, or open and diffuse. Spikelets small, sometimes minute, 1-flowered, or 
very rarely 2-4-flowered. Scales 3, rarely 4-6, membranous, acute or obtuse, rarely awn- 
pointed or short-awned, the 2 outer empty, the first shorter tlian the second, the remaining 
scale or scales longer or about equalling the second scale, enclosing a perfect flower, and a 
2-nerved, often deeply 2-cleft or 2-parted, palet which is equal in length to, or a little 
shorter than, the scale, rarely awned and exceeding it. Stamens 2 or 3. Styles short, 
distinct. Stigmas plumose. Kush Grass. 






POACEAE 



123 



1. S. vagi naeflor us . 



2. S. a^cr, 

3. S, canonrcns. 



4. S. attenuatiis. 

5. S, Drummondii, 

6. S, loagifoliua. 



13. S. BuckleyL 



Plants with no long rootstocks : stems tufted or single. 
Leaf-sheaths glabrous. 

Upper leaf-sheaths enclosing panicles which are usually concealed, or some- 
times partially protruding : terminal panicle contracted, narrow. 
Annual. 
Perennial. 

Flowering scale appressed-pubescent below with long hairs. 

Palet long-acuminate, sometimes almost awned, much exceeding 
the scale. 

Palet merely acute, about equalling the scale, rarely a little exceed- 
ing it. 
Flowering scale glabrous. 

Stems slender: panicle very slender, usually less than 5 mm. broad : 
spikelets 4 mm. long or less. 
Spikelets 3 mm. long. 
Spikelets 4 mm. long. 
Stems stout : panicle broader, usually 1 cm. wide : spikelets 5-6 mm. 
long. 
Upper leaf-sheaths not enclosing panicles. 

Panicle usually loose and open, its branches spreading or ascending, or if 
erect the panicle not elongated. 
Spikelets 2 mm. long or less. 

Panicle branches verticillate, at least the lower ones. 

Larger leaf-blades rarely exceeding 5 cm. in length. 7. iS. argutus. 

Larger leaf-blades 1 dm. long or more. 8. S. Bomingcnsis. 

Panicle branches scattered. 
Spikelets 3 mm. long or more. 

I'anicle branches verticillate. 9. S. ejujicldus. 

Panicle branches scattered. 

Empty scales very unequal, the first subulate, the second very 

broad. 10. S. heterolepis. 

Empty scales approximating each other in shape, the first lanceo- 
late. 
Basal leaf-blades 1.5 mm. wide or less. 11, S, Curiism. 

Basal leaf-blades 3 mm. wide or more. 12. S. Flon'danus. 

Panicle narrow and elongated, spike-like. 15. S. Jndicus. 

Leaf-sheaths with a tuft of long spreading hairs on each side of the apex, 14. S, cryptandrm. 

Plants with long rootstocks. 

Panicle loose and open : rootstocks slender. 16. S, ai^pcnjolius. 

Panicle contracted, spike-like: rootstocks stout : sand-binders. 17. S, Virginicas. 

1. Sporobolus vaglnaeflorus (Torr. ) Wood. Stems 2-6 dm. tall, erect, slender: 
leaf-blades 2 mm. wide or less, attenuate and slender above, the lower ones elongated, the 
upper 2-8 cm. long : terminal panicle 2-5 cm. long : spikelets 3.5-4.5 mm. long, the scales 
acuminate, the flowering one appressed-pubescent with long hairs. [6'. vrnjimieflorus var. 
minor Scribn.] 

In dry soil, Massachusetts and New York to Nebraska, Georgia and Florida. Summer and fall. 

2. Sporobolus ^sper (Michx. ) Kunth. Stems 6-12 dm. tall, erect : leaf-blades 7-35 
cm. long, 2-4 mm. wide, attenuate into a long slender involute tip : panicle 5-13 cm. 
long : spikelets 6-8 mm. long, the empty scales unequal, acute, the flowering scale ap- 
pressed-pubescent below, much longer than the second one and much exceeded by the 
long-acuniinate palet. 

In dry soil. New York to Illinois, Florida and Texas. Summer and fall. 

3. Sporobolus candvirens Nash. Stems 3-10 dm. tall, erect : leaf-blades 2.5 dm. 
long or less, 1-3 mm. wide, attenuate and filiform above : panicle 5-13 cm. long : spikelets 
5-6 mm. long, the scales acuminate, the empty ones unequal, the flowering scale appresserl- 
pubescent below with long hairs, about equalling or a little exceeded by tiie acute palet. 



In drj' sandy soil, Tennessee to Missouri, Kansas, Mississippi and Texas. Summer and fall. 

4. Sporobolus attenu^tus Nash. Stems tufted, slender, 5-7 dm. tall, erect : leaf- 



blades 4 dm. long or less, 1-2 mm. wide at the base, the upper portion filiform : panicle 
5-7 cm. long, very slender : spikelets 3 mm. long, the scales acuminate, the empty ones 
unequal, the second a little shorter than the glabrous flowering one which about equals 
the acute palet. 

In dry soil, Mississippi. Fall. 

5. Sporobolus Drummdndii (Trin. ) Vasey. Stems 5-10 dm. tall, erect, slender: 
leaf-blades 3 dm. long or less, 1-3 mm. wide, attenuate and filiform at the apex : panicle 
1-1.5 dm. long, slender: spikelets about 4 mm. long, the empty scales acute, the first a 
little shorter than the second, the flowering scale glabrous, acute or obtusish, longer than 
the second one and about equalling the acutish palet. 

In dry soil, Louisiana and Texas. Summer. 

6. Sporobolus longifolius (Torr.) Wood. Stems 4-12 dm. tall, stout, erect: leaf- 
blades 5 dm. long or less, 2-5 mm. wide : panicle 2-3 dm. long, usually more or less in- 
cluded in the upper leaf-sheath, sometimes entirely so : spikelets 5-6 mm. long, the scales 
obtuse, the first about J as long as the second, the flowering scale glabrous, considerably 
exceeding the second one, about equalling the palet or a little shorter or longer than it. 

In dry soil, Massachusetts to Iowa, Kansas and Arkansas. Fall. 



124 



POACEAE 



7. Sporobolus argutus (Nees) Kuntli. Stems 3 dm. tall or less, erect, or sometimes 
decumbent at the base : leaf-blades 2-5 cm. long, 2-4 ram. wide, acuminate : panicle 4-8 
cm. long, its branches at first appressed, finally widely spreading : spikelets 1.5-1.8 mm. 
long. 

On prairies, Kansas and Colorado to Louisiana and Texas, Also in Mexico and the West Indies, 
Summer and fall. 

8. Sporobolus Doming^nsls (Trin.) Kunth. Stems 3-5 dm. tall, erect : leaf-blades 
2 dm. long or less, 3-5 mm. wide, long-acuminate : panicle 8-15 cm. long, its branches at 
first erect, finally spreading : spikelets about 2 mm. long. 

In moist often brackish places, southern peninsular Florida. Also in Mexico and the West 
Indies. Summer. 

9. Sporobolus ejuncidus Nash. Stems tufted, 3-6 dm. tall, erect, slender : leaf- 
blades filiform or setaceous, the basal numerous, 1.5-3 dm. long, those on the stem few, 
2.5-8 cm. long : panicle 7-18 cm. long, open, its branches finally widely spreading : spike- 
lets 2.5-3 mm. long, purple, the empty scales very unequal, the first \-^ as long as the 
second, the flowering scale equalling the second and the obtuse palet. {_S. junceus (Michx, ) 
Kunth.] 

In dry sandy soil, Virginia to Florida and Texas. Spring to fall. 

10. Sporobolus heterdlepis A. Gray. Stems 3-10 dm. tall, erect : leaf-blades in- 
volute-setaceous, the basal ones about | as long as tlie stem, sometimes equalling it, those 
on the stem shorter : panicle 7-25 cm. long, its branches erect or ascending : spikelets 
4-5.5 mm. long, the empty scales unequal, acuminate, the lower subulate, about J as long 
as the broad second one, sometimes awn-pointed, the flowering scale obtuse or acute, ex- 
ceeded by the second or occasionally equalling it. 

In dry soil, Quebec to Assinilx)ia, Pennsylvania, Arkansas and Nebraska. Summer and fall. 

11. Sporobolus Curtis-sii (Vasey) Small. Stems tufted, 4-8 dm. tall, slender, erect, 
wiry : leaf-blades erect, 2.5 dm. long or less, 1-1.5 mm. wide, stiff, often involute : panicle 
1.5-2 dm. long, its branches ascending : spikelets 5-6 mm. long, the scales acute, the empty 
ones unequal, the second equalling or somewhat shorter than the flowering one. 

In sandy soil, Georgia, Florida and Alabama. Summer and fall. 

12. Sporobolus Floridanus Chapm. Stems 6-12 dm. tall, erect, stout : leaf-blades 
broad, flat, 4 dm. long or less, 4-5 mm. wide, linear, abruptly acute : panicle 2-4 dm. 
long, oblong, its branches ascending or erect-ascending : spikelets 4.5-5 mm. long, the 
empty scales acute, unequal, the second a little shorter than or about equalling the flower- 
ing scale M'hich is acute or obtusish and about as long as the palet. 

In sandy soil, Georgia and northern Florida. Fall. 

13. Sporobolus Buckleyi Vasey. Stems 5-8 dm. tall, erect : leaf-blades 3 dm. 
long or less, 3-7 mm. wide, flat, narrowed toward the base, long-acuminate above : panicle 
1.5-2.5 dm. long, its branches at first erect, finally ascending : spikelets 1.5 mm. long, the 
scales verv acute. 

In valleys, southern Texas. Also in Mexico. Summer. 

14. Sporobolus cryptdndrua (Torr. ) A. Gray. Stems 4-12 dm. tall, erect: leaf- 
sheaths with a dense tuft of long hairs on each side at the apex : blades 7-15 cm. long, 2-4 
mm. wide, flat, long-acuminate: panicle 1.5-2.5 dm. long, its branches spreading or 
ascending : spikelets 2-2.5 mm. long, the scales acute. 

In sandy soil, along the coast of New England and of the Great Lakes, to North Dakota, and in 
the interior in Missouri and Texas. Also in Mexico. Summer and fall. 

15. Sporobolus Indicus (L. ) E. Br. Stems 3-12 dm. tall, erect, tufted : leaf-blades 
2-6 mm. wide, attenuate into a long slender points, the basal ones 2-3 dm, long : panicle 
1-4 dm. long, usually much elongated, narrow, dense, spike-like: spikelets 1.5-2 mm. 
long. 

In fields and waste places, Virginia to Florida, Arkansas and California. Naturalized from trop- 
ical regions. Summer and fall. 

16. Sporobolus asperifolius Nees & Meyen. Stems 1.5-5 dm. tall, erect, decum- 
bent and branching at the base, from a slender rootstock : leaf-sheaths short, crowded and 
overlapping ; blades numerous, 2-9 cm. long, 2-3 mm. w^ide, very rough above : panicle 
7-20 cm. 'Jong, included at the base, rarely entirely exserted, the capillary branches 
spreading or ascending : spikelets sometimes 2-3-flowered, 1.5 mm. long. 

In dry soil, Assiniboia and British Columbia to Missouri, Texas and southern California. Also in 
Mexico. Summer and fall. 

17- Sporobolus Virginicos (L. ) Kunth. Stems 1.5-6 dm. tall, erect, from a stout 
rootstock : leaf-sheaths numerous, short, overlapping, crowded on the lower part of the 
stem ; blades 2.5-20 cm. long, 4 mm. wide or less at the base, distichous, long-acuminate, 



? 



-.s 



POACEAE 



125 



involute on the margins and at the summit : panicle 2.5-8 cm. long, 4-10 mm. wide, d 
and spike-like : spikelets 2-2.5 ram. long. 

On sandy shores, Virginia to Florida and Texas. Also in tropical America. Summer and fall. 

60. EPICAMPES Presl. 

Tall perennial grasses, with usually stout stems, flat leaf-blades, and contracted dense 
panicles. Spikelets 1-flowered ; empty scales about equal, very nearly as long as to some- 
what exceeding the thinner flowering scale which is frequently awned, the awn inserted 
just below the apex. Stamens 3. Styles distinct, short. Stigmas plumose. 

1. Epicampes Ugul^ta Scribn. Stems 8-12 dm. tall, stout: ligule pronounced, 1-2 
cm. long ; blades 5 dm. long or less, 3-5 mm. wide, usually folded : panicle 2.5-4 dm. 
long, 1.5-3 cm, wide : spikelets about 2.5 mm. long. 

In dry soil, central Texas to Arizona. Also in Mexico. Summer and fall. 

61. POLYPOQON Desf. 

Annual or perennial grasses, with usually decumbent or rarely erect stems, flat leaf- 
blades, and terminal panicles, generally very dense, which are cylindric and spike-like, or 
sometimes broa der and more lax. S pikelets articulated below the empty scales, crowded, 
1-flowered. Scales 3, the 2 outer empty, about equal in length, each terminating in an 
erect slender awn, the third scale smaller, thinner, often hyaline, enclosing a smaller palet 
and a perfect flower, entire, emarginate, or 2-toothed, awned or awn-pointed, when entire 
the awn terminal, otherwise dorsal, the awn slender, either long with a twisted base nnd 
geniculate at the middle, or short and erect, sometimes reduced to a mere point. Stamens 
1-3. Styles short, distinct. Stigmas plumose. Beard Grass. 

Panicle silky : awn of the empty scales of the spikelet 2-3 times as long as the 

scale. 1. P. Mo)i.'<pdi€H{iis. 

Panicle dull, often interrupted : awn of the empty scales of the spikelet about as 

long as the scale. 2. P. Uttoralis. 

1. Polypogon Monspeli6nsis (L. ) Desf. Stems 6 dm. tall or less, erect, from a 
usually decumbent base : leaf-blades 4-15 cm. long, 3-6 mm. Avide, rough : panicle 2-10 
cm. long, dense and spike-like : spikelets crowded, the empty scales about 2 mm, long, 
obtuse, slightly bifid, rough, bearing a bent awn 4-6 mm. long, the flowering scale much 
shorter, erose-truncate, hyaline, bearing a delicate awn about 0.5 mm. long, inserted below 
the apex. 

In waste places, New Hampshire to South Carolina, and very common in western North America 
from British Columbia to Mexico. Naturalized from Europe. Summer and fall. 

2. Polypogon llttoralls Sm. Stems tufted, 1.5-9 dm. tall, erect: leaf-blades erect, 
1.5 dm. long or less, 3-8 mm. wide : panicle 3-15 cm. long, 6-40 mm. wide : spikelets, 
exclusive of the awns, about 2 mm. long. 

In wet places. Louisiana; and from British Columbia to California. Naturalized from the Old 
World. Summer. 

62. CINNA L. 

Tall perennial grasses, with flat leaf-blades and long terminal contracted or open pan- 
icles, often nodding, its branches slender and usually drooping. Spikelets numerous, flat- 
tened, 1-flowered, the rachilla articulated below the empty scales. Scales 3, the 2 oiiter 
empty, persistent, keeled, acute, the third one similar in texture, stalked, bearing just 
below the somewhat obtuse apex a short awn or awn-like point, the scale enclosing a 
slightly smaller 1-nerved keeled palet, the keel minutely ciliate, and a perfect flower. 
Stamen 1, Styles short, distinct. Stigmas plumose. Reed Grass. 

Panicle contracted at maturity, its filiform branches erect, often drooping : spike- 
lets 4-5 mm. lonjr, the first scale much shorter than the second. l. c, arundimicca. 

Panicle open, its capillary branches flexuous and drooping : spikelets 3 mm. long, 

the first scale about equalling the second. 2. C. latifoHa. 

1. Cinna arundin^cea L. Stems 6-15 dm. tall : leaf-blades 1.5-3 dm. long, 4-14 
mm. wide, rough : panicle 1.5-3 dm. long, usually contracted, sometimes purple : sades 
of the spikelet acute, rough, the flowering scale slightly exceeded or equalled by the second, 
tisnally bearing an awn about 0.5 mm. long from the 2-t()0thed apex. 

In moist woods and swamps, Newfoundland to the Northwest Territorj-, North Carolina, Louisiana, 
Missouri and Texas. Summer and fall. 

2. Cinna latifolia (Trev. ) Griseb. Stems 6-12 dm. tall : leaf-blades 1-2.5 dm. long, 
4-12 mm. Avide, rough : panicle 1-2.5 dm. long, the capillary branches generally spreading 



126 



POACEAE 



and flexuous : scales of the spikelet rough, strongly liispid on the keel, the flowering one 
usually exceeded by the second and bearing a rough awn 1-2 mm. long from the 2-toothed 
apex. [C. aruiidinacea var. pendula A. Gray.] 

In damp woods, Newfoundland to New Jersey and British Columbia, and in the Alleghanies to 
North Carolina, and in the Rockies to Colorado and Utah. Also in northern Europe. Summer and fall. 

63. AGROSTIS L. 

Annual or perennial usually tufted grasses, with flat or setaceous leaf-blados and ter- 
minal often slender contracted or open panicles with numerous branches. Spikelets very 
numerous, small, 1-flowered, the rachilla articulated above the empty scales. Scales 3, the 
2 outer empty, persistent, membranous, keeled, acute, awnless, the third one shorter, 
thin-hyaline, awnless, or sometimes bearing a slender dorsal often geniculate awn, enclos- 
ing a perfect tlower and frequently also a short very thin hyaline palet rarely more than 
^ as long ai5 the scale, sometimes minute or wanting. Stamens usually 3. Styles distinct, 
very short. Stigmas pluuiose. Bent Grass. 

Palet of the spikelet conspicuous, at least % as long as the scale. 

Panicle open, its branches long and at' least some of them naked below : 



spikelets hispidulous on the keel only, 
icie dense and I 



1, A. alba. 



Panicle dense and contracted, its branches short and ascending or erect, spike- 
let-bearing to the very base : spikelets strongly hispidulous all over. 2. A. vertidUata. 
Palet inconspicuous, minute, or wanting. 

Flowering scale awnless, or very rarely bearing a short awn. 

Stems weak, usually decumbent and often prostrate at the base; leaf-blades 

lax : panicle oblong, the spikelets 1.5-2 mm. long. 3. A. perennans. 

Stems, ana usually also the leaf-blades, erect. 

Branches of the panicle capillary, elongated, commonly dividing above 
the middle. 
Spikelets 1.5-2 mm. long: leaf-blades short. 4. A. Jiyemalis. 

Spikelets 2.5-3 mm. long : leaf-blades elongated. 5. A, altissima. 

Branches of the panicle not elongated, dividing at or below the middle. 

Spikelets about 2 mm. long : a grass of low elevations. 6. A, Scribneriana. 

Spikelets 2.5-3 mm. long : a high mountain grass. 7. A. Novae- Angliae, 

Flowering scale awned. 

Awn glabrous, rigid, usually bent, less than twice as long as the spikelet. 

Branches of the panicle generally ascending : spikelets 2 mm. long. 8. A, canina. 

Branches of the panicle usually spreading ; spikelets 2.5-3 mm. long, 9. A, rubra. 

Awn very finely filiform, barbellate, at least twice as long as the spikelet. 10. A. EUiottiana. 

1. Agroatis dlba L. Stems 2-8 dm. tall, erect, or decumbent at the base, often 
stoloniferous : leaf-blades 5-20 cm. long, 2-6 mm, wide, rough or smooth ; panicle 5-23 
cm. long, usually open, or sometimes contracted after flowering, green or purplish : spike- 
lets 2-2.5 mm. long, the empty scales about equal, acute, hispidulous on the keel. 

In fields and meadows, nearly throughout North America. Summer. Red-top, 

2. Agrostis verticill^ta Vill. Stems tufted, 8 dm. tall or less : leaf-blades erect, 
linear to lanceolate, 1.5 dm. long or less, flat, very rough, 2-8 mm. wide: panicle 4-12 
cm. long, dense, often interrupted, its short branches ascending or erect, densely spikelet- 
bearing to the base : spikelets 1.5-2 mm. long, the empty scales strongly hispidulous. 

In moist places, Texas to Arizona. Also in Mexico. Spring to fall. 

3. Agrostis perennans (Walt.) Tuckerm. Stems 3-8 dm. long from a decumbent 
or prostrate base, weak, slender, simple, or sparingly branched above : leaf-blades 5-15 
cm. long, 2-4 mm. wide, lax, rough : panicle 1-2 dm. long, open, oblong, its branches 
widely spreading, the branchlets and pedicels divergent: spikelets 1.5-2 mm. long, the 
empty scales hispidulous on the keel. 

In woods, New Hampshire and Massachusetts to Ohio, Kentucky and North Carolina. Summer 
and fall. 

4. Agrostis hyemklls (Walt.). B.S.P. Stems 3-6 dm. tall, slender: leaf-blades 
5-13 cm. long, 1-3 mm. wide, usually erect, roughish : panicle 1.5-6 dm. long, usually 
purplish, the very rough capillary branches ascending or spreading, often drooping, the 
lower ones 7-15 cm. long : spikelets 1.5-2 mm. long. [A. scabra Willd.] 

In dry or moist soil, throughout nearly the whole of North America. Summer. 

5. Agrostis altissima (Walt.) Tuckerm. Stems 6-12 dm. tall, erect: leaf-blades 
elongated, 1.5-3 dm. long, 2-3 mm. wide, rough : panicle 2-2.5 dm. long, its branches 
ascending or erect, the lower 5-10 cm. long, spikelet-bearing at the end : spikelets 2.5-3 
inm. long, occasionally bearing a short awn. [-4. elata Trin.] 

In sandy swamps, New Jersey to Florida and Alabama. Summer and fall. 

6. Agrostis Scribnerikna Nash. Stems 3-9 dm. tall, erect, tufted, rather slender : 
leaf-blades 1-2.5 dm, long, 2-6 mm. wide, rough: panicle 1-2,5 dm. long, its ascending 
branches 3.5-8 cm, long: spikelets about 2 mm. long, on appressed pedicels. [Agrostis 
intennedia Scribn., not Balb.] 

In dry soil, Massachusetts to New York, Tennessee and Missouri. Summer and fall. 



-J 



POACEAE 



127 



7. Agrostis Novae Angliae Tuckerm. Stems 2-4 dm, tall, erect, tufted : loaf-blades 
2.0-9 cm. \ongj 2 mm. wide or less, erect, generally involute, rough : 2>ani('le 1-2 dm, long, 
open, the branches spreading or ascending : spikelets 2.5-3 mm. long, very liispidulous on 
the keel. 

In dry soil, Newfoundland and on the high mountains of Xew En|:,^]and, Xew Vorlc and North 
Carolina. Summer. 

8. Agrostis canina L. Stems 3-6 dm. tall, erect, slender: leaf -blades 2.5-8 cm. 
long, 2 mm. wide or less, rough : panicle 5-18 cm. long, contracted in fruit, its brandies 
slender, naked below, ascending or spreading in flower : spikelets 2 mm. long, on ap- 
pressed pedicels, the flowering scale with an awn 2-4 mm. long inserted just above the 
middle. 

In meadows, Newfoundland and Alaska to Pennsylvania and Tennessee. Naturalized fn»m 
Europe in the South. Summer and fall. 

9. Agrostis rubra L. Stems 1.5-6 dm. tall, erect: leaf-blades 5-10 cm. long, 1-3 
mm. wide : panicle 6-13 cm. long, open, the branches usually widely spreading and more 
or less flexuous, rarely erect : spikelets 2.5-3 mm. long, the flowering scale bearing a gen- 
erally bent awn 4-5 mm. long and inserted below the middle. 

In drj' or wet soil, summits of the highest mountains in New England, New York and North 
.Carolina. Summer. 

10. Agrostis EUiotti^na Schult. Stems 1-4 dm. tall, erect, slender, tufted : leaf- 
blades 1-5 cm. long, 2 mm. wide or levSS, rough : panicle 5-13 cm. long, usually narrow, 
sometimes open, the branches slender, naked below, erect or ascending : spikelets 1.5 mm. 
long, the third scale bearing a very finely filiform flexuous barbellate awn 2-4 times its 
length, inserted just below the apex. [_Agrostis arachnoides Ell.] 

In dry soil, South Carolina to Kentucky, Florida and Texas. Spring and summer. 

64. GASTRIDIUM Beauv. 

Tufted annual grasses, with flat leaf-blades and spike-like dense cyliudric shining 
panicles. Spikelets numerous, crowded, 1-flowered, the rachilla articulated above the 
empty scales and extending beyond the flower. Scales 3, the 2 outer empty, unequal, per- 
sistent, narrow, keeled above, acute, sometimes short-awned, the third scale much shorter, 



thinly hyaline, broad, denticulate at the truncate apex, awnless, or sometimes bearing an 
awn below the apex, enclosing a narrow somewhat shorter palet and a perfect flower. 
Stamens 3. Styles short, distinct. Stigmas plumose. 

1. Gastridium lendfgerum (L. ) Gaud. Stems 1.5-5 dm. tall, erect, or decumbent 
at the base, often branched : leaf-blades erect, 1 dm. long or less, 2-4 mm. wide : panicle 
3-13 cm. long, dense, 5-13 mm. in diameter : spikelets, exclusive of the awn, 3-4 mm. long. 

In dry places, Texas. Also in Oregon and California. Naturalized from Europe. Summer. 

65. CALAMAGROSTIS Adans. 

Erect usually perennial grasses, with generally flat, sometimes involute leaf -blades, and 
terminal contracted or open panicles. Spikelets numerous, 1 -flowered, commonly small, 
the rachilla usually prolonged beyond the flower, the prolongation either pilose through- 
out, the usual state, or with a terminal tuft of long hairs. Scales 3, the 2 outer empty, 
persistent, narrow, keeled, acute or acuminate, the third scale much shorter than the others, 
very thickly hyaline, with a basal ring of hairs which are from one-half as long as the scale 
to somewhat exceeding it, rarely very short or almost wanting, bearing a usually delicate 
dorsal awn which is rarely twisted at the base, and enclosing a small narrow thinly hyaline 



palet and a perfect flower. Stamens 3. Styles short, distinct. Stigmas plumose. 



Prolongation of the rachilla of the spikelet hairy throughout : spikelets a-4 mm. long. 1 . C, 
Prolongation of the rachilla of the spikelet hairy at the summit : spikelets 6-8 mm. long. 2. C, ci 



Canadoisin. 
cinnoidea. 



1. Calamagrostls Canadensis (Michx.) Beauv. Stems 6-15 dm. tall, smooth or 
somewhat rough : leaf-blades 1-3 dm. long or more, 2-8 mm. wide, rough : panicle 1-2 
dm. long, open, usually purplish, its branches spreading or ascending, naked at the base : 
spikelets 3-3.5 mm. long ; flowering scale with a delicate awn, the basal hairs equalling or 
a little shorter than the scale. 

In swamps and wet soil, Prince Edward Island to British Columbia, Kew Jersey, Ohio, Iowa, Utah 
and Oregon.— Represented in our " ""- ^'-^ *"''■' ^^ ^'--^^ r>„^^i:^o k,. n nr.^^r^^.1. 

acujnindta Vasey, which differs in 
in the larerer smkplpf« whir»h arp ^ 




128 



poaceap: 



2. Calamagrostis cinnoides (Mulil. ) Scribn. Stems 9-15 dm. lull, erect: leaf- 
blades 1-3 dm. long or more, 4-10 mm. wide, rough : panicle 7-18 cm. long, contracted, 
its branches erect : spikelets 6-8 mm. long, the scales very hispidulous, the outer ones 
about equal, acuminate and awn-pointed, the flowering scale obtuse, the basal hairs from 
^— § its length, the awn stout, exceeding or equalling the scale. [G Nuttalliana Steud.] 

In moist soil. New Hampshire and Massachusetts to Pennsylvania and Georgia. Summer. 

66. AMMOPHILA Host. 

Tall perennial grasses, with flat leaf-blades, M'hich are often convolute above, and 

dense spike-like panicles. Spikelets l-flowered, the rachilla prolonged beyond the flower 

and hairy. Scales 3, rigid, chartaceous, acute, keeled ; flowering scale 5-nerved, with a 

ring of short hairs at the base. Stamens 3. Styles distinct. Stigmas plumose. 

1. Ammophila arenaiia (L.) Link. Stems 6-12 dm. tall, erect, rigid, stout, arisin 
from a long branching rootstock : leaf*blades 1.5-3 dm. long or more, rigid, attenuated 
into a long slender involute point, rough above : panicle 1-3 dm. long, 1-1.5 cm. in diam- 
eter : spikelets 10-12 mm. long, the scales hispidulous, the flowering scale usually with the 
rudiment of an awn just below the apex. \_Calmnagrosti$ arenaria (L. ) Koth.] 

In sands along the seacoast, New Brunswick to North Carolina, and inland along the shores of the 
Great Lakes. Summer and fall. Sea Sand Reed, 

67. CALAMOVILFA Hack. 

Tall perennial grasses, with horizontal rootstocks, elongated narrow flat leaf-blades^ 
involute at the apex, and contracted or open panicles. Spikelets flattened, 1-flowered, 
crowded, the rachilla articulated above the empty scales and not prolonged beyond the 
flower. Scales 3, rigid, chartaceous, awnless, keeled, 1-nerved, the 2 outer empty, unequal^ 
persistent, the third scale with a ring of long hairs at the base, enclosing a 2-keeled palet 
and a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. Reed Grass. 

1. Calamovilfa Curtissii Vasey. Stems 8-12 dm. tall, erect : leaf-blades 4 dm. long 
or less, 2-3 mm. wide : panicle 1.5-3 dm. long, narrow, 1.5-2 cm. in diameter, its' branches 
erect : spikelets about 5 mm. long. [^Calamagrostis Curtissii Vasey.] 

In dry or moist pine lands along the Indian River, Florida. Summer. 

68. HOLCUS L. 

Annual or perennial grasses, with usually flat leaf-blades and terminal spike-like con- 

tracted or open often interrupted panicles, Spikelets crowded, 2-flowered, the lower flower 

perfect, the upper one staminate, the rachilla articulated below the empty scales. Scales 

4, the 2 outer empty, keeled, the first 1-nerved, acute, the second broader, 3-nerved, acute 

or short -awned, the third and fourth scales shorter than the second, membranous, at length 

rigid, enclosing flowers, the former awnless, the latter bearing a slender dorsal awn which 

is often hooked when dry; palet narrow, 2-keeled. Stamens 3. Styles distinct. Stigmas^ 

plumose. Velvet Grass. 

.1, Holcus lan^tus L. Softly and densely pubescent. Stems 4-9 dm. tall, erect, 
tufted : leaf-blades 2.5-15 cm. long, 4-12 mm. wide : spikelets 4 mm. long, the empty 
scales white-villous, the upper one awn -pointed, the flowering scales 2 mm. long, glabrous, 
shining, the upper one 2-toothed and bearing a finally hooked awn Just below the apex. 

In meadows, fields and waste places, Nova Scotia to Ontario, Illinois, North Carolina and Tennes-^ 
Also on the Pacific Coast. Naturalized from Europe. Summer. Velvet Grass, 

69. AIRA L. 

Mostly annual grasses, with narrow leaf-blades and contracted or open panicles. 
Spikelets small, 2-flowered, both flowers perfect. Scales 4, the lower 2 empty, thin-mem-- 
branous, acute, subequal, persistent, the flowering scales usually close together on the 
rachilla, hyaline, mucronate or 2-toothed, bearing a delicate awn inserted just below the 
middle. Stamens 3. Stigmas plumose. Hair Grass. 

1. Aira caryophyllea L. Glabrous throughout. Stems 1-2.5 dm. tall, erect, from 
an annual root, slender : leaf-blades 1-5 cm. long, involute-setaceous : panicle silvery, 
shining, 2-10 cm. long, open, its branches spreading or ascending : spikelets 2-2.5 mm. 
long, the empty scales acute, the flowering scales very acute, 2-toothed, 2 mm. long, bear- 
ing an awn 3-4 mm. long. 

In fields and waste places, Massachusetts to North Carolina. Also on the Pacific Coast. Natural- 
ized from Europe. Spring and summer. 



1 



J 



"1 

-• 

-! 



'A 



■;i 



.) 



POACEAE 



129 



70. DESCHAMPSIA Bcnuv. 



riv- 



Perennial gmsses, with narrow convolute or flat luaf-blades and terminal contracted or 
open panicles. Spikelets 2-floAvered, the rachilla articulated above the empty scales and pro- 
longed beyond the flowers. Scales 4, the 2 outer empty, persistent, keeled, acute, mem- 
branous, usually somewhat shining, the flowering scales thin-membranous, almost hyaline, 
entire or toothed, acute, obtuse, or truncate and denticulate at the apex, eacli bearing a 
slender dorsal straight or geniculate awn Avliich is twisted at the base ; palet narrow, 2- 
nerved. Stamens 3. Styles distinct. Stigmas plumose. Hair Grass. 

Flowering scales about 2.5 mm. long, erose-truncate : leaf-blades fiat. 1. i>. carap'itom. 

Flowering scales about 4 mm. long, acute or obtuse : leaf-blades involute. 2. />. flexMomi. 

1. Deschampsia caespitosa (L. ) Eeauv. Stems tul\ed, 6-12 dm. tall, erect: Xva^- 
blades flat, 2-3 ram. wide, rough above, the basal ones numerous, |-J as long as the stem, 
those on the stem 5-15 cm. long : panicle open, 7-23 cm. long, its branches spreading or 
ascending, naked at the base : spikelets 3.5-4 mm. long, the flowering scales about 2.5 mm. 
long, erose-truncate at the apex, the awns somewhat sliorter or a little longer than the scale. 

In wet soib Newfoundland to Alaska, New Jersey, Illinois, Minnesota and in the mountains to 
North Carolina, New Mexico and California. Also in Europe and Asia. Summer, 

2. Deschampsia flexuosa ( L. ) Trin. Stems tufted, 3-8 dm. tall, erect, slender: 
leaf -blades involute-setaceous, rough above, the basal very numerous, \ as long as the stem 
or less, those on the stem 2-8 cm. long : panicle open, 5-20 cm. long, the branches spread- 
ing to nearly erect, naked at the base, flexnous : spikelets 4.5-5 mm. long, the flowerhig 
scales about 4 mm. long, acutely toothed at tlie apex, the awns bent and twisted, much ex 
ceeding the scale. 

In dry soil, Greenland and Newfoundland to Ontario, Michigan, North Carolina and Tenntssfo. 
Also in Eurox>e. Summer. 

71. TRISETUM Pers. 

Annual or perennial tufted grasses, with flat leaf-blades and terminal spike-like con- 
tracted or open panicles. Spikelets usually 2-flowered, rarely 3-6-flowered, the flowers 
perfect, or the upper one staminate, the rachilla glabrous or pilose, articulated between 
the flowering scales and prolonged beyond them. Scales 4, rarely 5-8, keeled, the 2 outer 
empty, membranous, unequal, acute, entire at the apex, awnlcss, persistent, the flowering, 
scales usually shorter, sometimes longer, 2-toothed at the apex, the teeth acuminate and 
often terminating in a bristle or slender awn, awned, or the lower flowering scale rarely 
awnless, the awn often twisted, inserted below the apex and arising between the teeth ; palet 
hyaline, 2-toothed. Stamens 3. Styles distinct. Stigmas plumose. 

Flowering scales each bearing a long awn. 

Empty scales shining, 1-nerved, or the second one 3-nerved. 
Panicle spike-like, dense, its branches short and appressed. 
Panicle loose and open, its branches long and slender, erect or ascending. 
Empty scales not shining, very strongly nerved, the first 3-nerved, the second 
5-nerved . 
Awn of the flowering scales inserted about % way below the apex : teeth 

of the flowering scales euneate. 
Awn of the flowering scales inserted about the middle : teeth of the flower- 
ing scales subulate. 
Lower flowering scale not bearing a long awn, a remnant sometimes'present. 
Second empty scale less than 3 mm. long : awn of the flowering scales 1-2 mm. 

long. 
Second empty scale 4-5 mm. long : awn of the flowering scales exceeding 3 
mm. in length. 
Empty scales dissimilar, the first much narroMer than the second, 1-nerved, 

or sometimes 3-nerved at the base : leaf-blades 1 dm. long or less. 6. T. Pennsyhaniatm. 

Empty scales similar, the first about as broad as the second, strongly 3- 

nerved : leaf-blades 1.5-2 dm. long. - 7. T, Ludoticiannm, 

1. Trisetum subapic^tum (L, ) Beauv. Softly pubescent or glabrous in some or all 
of its parts. Stems 1-6 dm. tall, erect : leaf-blades 2-10 cm. long, 1-4 mm. wide : pan- 
icle spike-like, 2-13 cm. long, oval to oblong, sometimes interrupted below : spikelets 2-3- 
flowered, the empty scales hispidulous on the keel, the second one about 5 mm. long, the 
flowering scales 4-5 mm. long, acuminate, hispidulous, each bearing a long bent and some- 
what twisted awn. [T. molle Kunth.] 

In dry or rocky places. Labrador to Alaska, and in the mountains to North Carolina, New Mexico 
and California. Also in Europe and Asia. Summer and fall. 



False Oat. 


1. 

2. 


T. snbspicaturn, 
'J\ flavesccns. 


3. 


T. Haim. 


4. 


T. interrupium. 


5. 


T. aridatiim. 



2. Trisetum flav6scens (L. ) K. & S. Stems 4-8 dm. tall, erect, glabrous: leaf- 
^heaths pubescent ; blades 4-13 cm, long, 2-6 mm. wide, rough : jianicle open, 5-13 cm. 

9 



130 



POACEAE 



long, its branches ascending or erect, somewliat flexuous, naked below : spikelets 3-4- 
flowered, the first empty scale about ^ as long as the second which is about 5 mm. long, the 
flowering scales 5-G mm. long, hispidulous, eacli bearing a long, bent and twLsted awn. 

In waste places and fields, Missouri, Kansas and Mississippi. Xaturalized from Europe or Asia. 
Summer. 

3. Trisetum Hallii Scribn. Stems tufted, 1.5-5 dm. tall, slender: leaf-blades 3-13 
cm. long, 2-3 mm. wide, rough, flat, or somewhat involute : panicle contracted, 3-15 cm. 
long, its branches erect or nearly so : spikelets 4-5 mm. long, exclusive of the awns, the 
first scale much narrower and almost as long as the second. 

On prairies, Texas. Spring. 

4. Trisetum intemiptum Backl. Stems tufted, 5 dm. tall or less, slender : leaf- 
sheaths glabrous or pubescent ; blades flat or involute, rough, 8 cm. long or less, 1-2 mm. 
wide : panicle 4-13 cm. long, its branches erect or nearly so : spikelets 4-5 mm. long, ex- 
clusive of the awns, the first scale narrower than the second but about as long. 

In dry soil, Texas. Spring. 

5. Trisetum aristatum (Scribn. & Mer, ) Nash. Stems 4-6 dm. tall, erect, slen- 
der: leaf-blades 1.5 dm. long or less, 1-2 mm. wide, roughish : panicle slender, 1.5-2.5 
dm. long, its branches erect or nearly so, the larger ones 6-8 cm, long : spikelets of 4 or 5 
scales, 4.5-5 mm. long, exclusive of the awns, the first scale linear, several times narrower 
than the broad second scale. 

In moist or dry soil, Nortli Carolina. Sumtaer. 

6. Trisetum PennsylvAnicum (L. ) B.S.P. Stems 3-9 dm. tall, erect, slender and 
often weak : leaf-sheaths sometimes rough ; blades 1 dm. long or less, 1-4 mm. wide, 
rough : panicle 6-15 cm. long, its branches erect or ascending : spikelets of four scales, 
the empty ones about equal, the first a little shorter than the second, the flowering scales 
4-5 ram. long, the second one hispidulous or nearly glabrous. [T. palnstre Torr.] 

In swamps and wet meadows, New York to Virginia, Tennessee and Florida. Spring and summer. 

7. Triset.um Ludoviclknum Vasey. Stems 6-9 dm. long, weak : leaf-blades flat, the 
larger ones 1.5-2 dm. long, 4-6 mm. Avide, rough : panicle 1.5-2.5 dm. long, its branches 
erect or nearly so : spikelets usually of 4 scales, the first a little shorter than the second, 
the second flowering scale strongly hispidulous. 



In wet places, Louisiana. Spring. 



72. AVENA L. 



Annual or perennial grasses, varying in habit, with usually flat leaf-blades and terminal 
contracted or open panicles. Spikelets genei'ally large, erect or pendvdous, usually 2- 
several-flowered, rarely 1-flowered, the rachilla articulated between the fertile flowers, the 
lower flowers perfect, the upper ones often staminate or wanting. Scales 4-several, rarely 
3, the 2 outer empty, membranous, exceeding or shorter than the flowering scales, persist- 
ent ; the flowering scales 5-9-nerved, rounded on the back, the apex frequently shortly 2- 
toothed, the scales enclosing perfect flowers and bearing a dorsal twisted geniculate awn^ 
tlie upper empty ones or those infolding staminate flowers awnless ; palet 2-cleft or 2- 
toothed, narrow. Stamens 3. Styles distinct. Grain deeply furrowed, usually pubescent. 

1. Avena sativa L. Annual. Stems 8-15 dm. tall: leaf -blades flat, 2.5 dm. long 
or less, 5-10 mm. wide or more : panicle usuallv 1.5-4 dm. loner, its branches erect or ascend- 



ing : empty scales of the spikelet 2-3 cm. long, acuminate, the flowering ones shorter, 
awned or awnless. 

In fields and waste places, escaped from cultivation nearly everywhere in civilized North America 
Summer. Oat. 

73. ARRHENATHERUM Beauv. 

Tall perennial grasses, with flat leaf-blades and terminal open or contracted panicles. 
Spikelets 2-flowered, the lower flower staminate, the upperone perfect or pistillate, the rachilla 
articulated above the empty scales and prolonged beyond the flowers. Scales 4, the 2 outer 
empty, persistent, thin-membranous, keeled, the flowering scales more rigid, somewhat 
toothed at the apex, the lower one bearing near the base a long dorsal twisted and genicu- 
late awn, the upper scale awnless, or short-awned below the apex ; palet 2-keeled, hyaline, 
narrow. Stamens 3. Styles short, distinct. Stigmas plumose. Grain hardly sulcate. 

1. Arrhenatherum el^tius (L.) Beauv. Stems 6-12 dm. tall, erect; leaf-blades 
6-30 cm, long, 2-8 mm. wide, rough : panicle 1-3 dm. long, its branches erect : empty 



POACEAE 



131 



scales of the spikelet unequal, the fn'st shorter than the second which is ahout 8 mm. long, 
the flowering scales about 8 mm. long. [A, avenaceum Beauv.] 



Tn fiel<i? and waste places. Maine and Ontario to Georgia, Tennessee and Nebraska 
nfic Coast. Xatunili/ed from Europe. Summer. Oat Grass. 



Also on the 



74. DANTHONIA DC. 

Lrsualiy perennial grasses, various in habit, with flat or convolute leaf-blades anJ ter- 
minal dense and contracted or open diffuse panicles. Spikelets 3-many-flowered, tlie flow- 
ers perfect or the uj^per ones staminate, the rachilla pilose, articulated between the scales 
and prolonged beyond them. Scales 5-many, the 2 outer empty, persistent, usually ex- 
tending beyond the flowering scales, rarely shorter, keeled, acute or acuminate, the flower- 
ing scales rounded on the back, the margins often ciliate, 2-toothed at the apex, the teeth 
often awned, with an awn arising between the teeth which is more or less flattened and 
very often twisted at the base and frequently geniculate, the remaining scales often small 
and enclosing a palet only, or empty ; palet obtuse or 2-toothed, 2-keeled, hyaline. Sta- 
mens 3. Styles distinct. Stigmas plumose. Wild Oat Grass. 

Empty seales of the spikelet 1.25 cm. long or less : leaf-sheaths glabrous, or sometimes 
sparinp:ly pubescent at the base. 

Teetli of the flowering scale about 1 mm. long, acute : leaf-blades of the stem short : 
panicle contracted. 

■ Teeth of the flowering scale 2-3 mm. long, awned : leaf-blades of the stem elon- 
gated : panicle usually open. 
Empty scales more than 1.25 cm. long. 
Leaf-sheaths and flowering scales villous. 



1. J), spicata, 

2. D. compressa. 

3. D, sencea. 



Leaf-sheaths glabrous : flowering scales pilose on the margins. 4 i>. epilis, 

1. Danthonia spicata (L. ) Beauv. Stems 3-8 dm. tall, erect, nearly round : leaf- 
sheaths glabrous, or often sparingly pubescent below ; blades rough, 2 mm. wide or less, 
usually involute, the lower ones 1-1.5 dm. long: panicle 2-5 cm. long, its branches, as 
well as the pedicels, erect or ascending : spikelets 5-8-flowpred, the empty scales 8-10 mm. 
long, the flowering scales broadly oblong, sparingly appressed-pubescent with silky hairs. 

In dry soil, Newfoundland, Quebec and North Dakota to North Carolina, Kansas and Louisiana. 
Summer and fall. 

2. Danthonia compr^ssa Austin. Stems 4-9 dm. tall, flattened, erect : leaf-blades 
2 mm. wide or less, the lower ones 1.6-2 dm. long : panicle open, 6-10 cm. long, the lower 
branches usually spreading : spikelets 5-10-flowered, the empty scales 10-12 mm. long, the 
flowering scales oblong, with a ring of short hairs at the base, a ppreased -pubescent with 
silky hairs. 

In woods, Maine and Vermont to North Carolina and Tennessee. Summer and fall. 

3. Danthonia sericea Nutt. Stems 4-9 dm. tall : leaf-sheaths villous ; blades rough 
and more or less villous, 2-3 mm. wide, the basal ones usually flexuous, those on the stem 
2'-10 cm. long, erect : panicle 6-12 cm. long, contracted, the branches erect or ascending : 
spikelets 4-10-flowered, the empty scales 14-16 mm. long, the flowering scales oblong, 
strongly pubescent with long silky hairs, the teeth 2-3 mm. long, acuminate, awned. 

In dry sandy soil, Massachusetts to New Jersey and Florida. Spring and summer. 

4. Danthonia Spills Scribn. Stems tufted, erect, 4-7 dm. tall, slightly roughened 
just below the panicle and puberulent below the brown nodes : leaf-blades 2-4 mm. wide, 
erect, those on the sterile shoots 1.5 dm. long or more, those on the stem 5-10 cm. long : 
panicle 5-8 cm. long, contracted : spikelets 5-10-flowered, the empty scales acuminate, the 
flowering ones 5-6 mm. long to the base of the teeth, pilose on the margins below and 
sometimes sparingly so on the midnerve at the base, the teeth, including the awn, 2-3 mm. 
long. [/). glabra Nash, not Philippi.] 

In swamps, southern New Jersey to Georgia. Spring and summer. 

75. CAPRIOLA Adans. 

Perennial usually stoloniferous grasses, the stems as well as the stolons often creeping, 
with flat usually short leaf-blades and spicate inflorescence, the spikes terminal. Spikelets 
1 -flowered, small, sessile, alternate in 2 rows on one side of the continuous rachis. Scales 
3, the 2 outer empty, persistent, thin, keeled, acute or obtuse, awnless, the flowering scale 
membranous, broader, its keel ciliate, awnless, enclosing a 2-keeled hyaline palet and a 
perfect flower. Stamens 3. Styles distinct. Stigmas plumose. {Cynodon L. C, Rich.] 

1. Capriola DActylon (L.) Kuntze. Stems 1-3 dm. tall, erect, from long creeping 
and branching rootstocks : leaf-sheaths glabrous or somewhat pubescent, crowded at the 



132 



POACEAE 



base of the stems and along the stolons ; blades 2.5-5 cm. long, 2-4 mm. wide, flat, rigid, 
rough above : spikes 4 or 5, digitate, 1-5 cm. long : spikelets 2 mm. long, the outer scales 
hispid on the keel. [^Cynodon Dactylon (L. ) Pcrs.] 

In fields and waste places, southern New York to Pennsylvania, Tennessee. Florida and Texas. 
Naturalized from Europe. Summer and fall. Bermuda Grass. 

76. SPARTINA Schreb. 

Often tall grasses, with flat or convolute leaf-blades and spicate inflore^icenee, the spikes 
one-sided, the rachis extending beyond the spikelets. Spikelets 1-flowered, sessile or 
nearly so, much crowded and imbricated in 2 rows. Scales 3, firm-membranous, the 2 
outer empty, narrow, very unequal, keeled, the flowering scale equalling or a little longer 
and broader than the second scale ; palet thin or almost hyaline, enclosing a perfect flower, 
obscurely 2-nerved, scarcely included in the scale which it often slightly exceeds. Stamens 
3. Styles elongated. Stigmas 2, thread-like, papillose or shortly plumose. Marsh Grass. 



Second scale long-awned. 
Second scale awnless. 

First scale strotigly hispid on the keel. 
Leaf-blades wide (1-2.5 cm.), flat. 
Leaf-blades narrow (6 mm. or less) involute, at least when dry. 

First scale less than %^ as long as the second : spikes usually few, erect or 
ascending. 



1. S, cynomr Oldest, 



2. S. polydac.hya. 



3. <5?. patens. 



First scale about % as long as the second : spikes numerous, appressed. 4. S.juneiformis. 



First scale not hispid on the keel. 



6. 8, atricta. 



1. Spartlna cynosuroides (L. ) Willd. Stems 6-18 dm. tall: leaf -blades 3 dm. 
long or more, 6-14 mm. wide, attenuate into long slender tips : spikes 5-30, ascending or 
erect, 5-13 cm. long: spikelets strongly imbricated, 12-14 mm. long, the empty seal 
strongly hispid on the keel. 

In swamps and streams of brackish or fresh water. Nova Scotia to Assiniboia, New Jersey and 
Texas. Summer and fall. 

2. Spartlna polystdchya (Michx. ) Ell. Stems 1-3 m. tall, stout ; leaf-blades 3 dm. 
long or more, 1-2.5 cm. wide, flat, attenuate into long slender tips: spikes 20-50, as- 
cending, 5-10 cm. long : spikelets much imbricated, 8-10 mm. long, the empty scales 
strongly hispid on the keel. 

In salt and brackish marshes, New Jersey to Florida. Summer and fall. White Rush. Sai.t 
Reed Grass. 

3. Spartlna pitens (Ait.) Muhl, Stems 3-9 dm. tall^ usually from a branching and 
decumbent base: leaf-blades L5-3 dm. long, 2-4 mm. wide, involute, attenuate into long 
tips: spikes 2-10, 2.5-5 cm. long, usually ascending: spikelets 6-8 mm. long, the empty 
scales hispid on the keel. \_S, juncea Willd.] 

On salt meadows, Newfoundland and Nova Scotia to Florida and Texas. Summer and fall. Salt 
Meadow Grass. White Rush. 

4. Spartlna juncifdimis Engelm. & Gray. Stems tufted, stout, rigid, 3-10 dm. 
tall : leaf -sheaths thick, hard, the lower ones shining ; blades involute, 5 dm. long or less : 
panicle 1-2 dm. long, narrow, strict, its branches 3-4 cm. long : spikelets about 7 mm. 
long, the first scale at least | as long as the third scale. 

In sandy or alluvial soil, Florida to Texas. Summer and fall. 

5. Spartlna stifcta (Ait.) Roth. Stems 3-10 dm. tall, erect, usually stout: leaf- 
blades 5 dm. long or less : panicle 1-3 dm., long, its branches appressed, 4-10 cm. long : 
spikelets 1-1.5 cm. long, glabrous or appressed-pubescent. [& glabra MuhL] 

In salt or brackish marshes, Maine to Florida, Texas and California. Summer and fall. 



77. CAMPULOSUS Desv. 



Often tall perennial grasses, with narrow flat or convolute leaf-blades and usually a 
terminal straight or curved dense spike. Spikes rarely 2 or 3. Spikelets 1-2-flowered, if 
the latter the upper flower staminate, sessile, crowded in 2 rows. Scales 6 or 7, the lower 
4 empty, the first small, keeled, awnless, the second larger than the others, membranous or 
rigid, acute or 2-cleft, generally bearing near the middle a dorsal often stout and usually 
horizontal awn, or the awn sometimes reduced to a tubercle, the third, fourth and fifth scales 
awned, more delicate than the second, the 2 former empty or enclosing palets, the fifth scale 
enclosing a palet and a perfect flower, the remaining scales narrow, empty or enclosing 
palets, the first also rarely a staminate flower. Stamens 3. Styles distinct. Stigmas 
plumose. Toothache Grass. 



POACEAE 



183 



glands. 



Spikes stout, the sf)ikelets at right-angles totherachis : second scale with a row of 

glands each side of the midnerve. 1. c. aromaticiis. 

Spikes slender, the spikelets diverging from the rachis : second scale without 

2. C. ChapadensU. 

1. Campulosus aromdticus (Walt. ) Scribn. Stems 9-12 dm. tall, erect : leaf-blades 
1.5 dm, long or less, 2-4 mm. wide, flat or involute : spikes 5-10 cm. long : spikelets about 
6 mm. long. Plant pungent to the taste. [^Ctenium Americanum Spreng.] 

In moist soil in pine lands, Virginia to Florida and Mississippi. Summer and fall. 

2. CampulosuB Chapad^nsis Trin. Stems slender, 6-10 dm. tall : leaf-blades flat, 
2 dm. long or less, 1-3 mm. wide : spikes slender, 5-15 cm. long : spikelets 5-6 mm. long, 
exclusive of the awns. 

In pine woods, Florida. Also in Brazil, Summer and fall. 



2. C. tenuispica. 



4. C hrevispica. 



78. CHLORIS Sw. 

Usually perennial grasses, with flat leaf-blades and spicate inflorescence, the spikes ver- 
ticillate or approximate. Spikelets 1-flowered, sessile, crowded in 2 rows, the rachilla 
prolonged beyond the flower. Scales usually 4, sometimes 5, or occasionally more, the 2 
lower empty, persistent, unequal, keeled, narrow, acute or acuminate, awnless or rarely 
awn-pointed, the third scale acute, usually long awned, rarely nearly awnless, enclosing a 
perfect flower and a folded 2-keeled palet, the remaining scale or scales commonly empty 
and usually awned. Stamens 3. Styles distinct. Stigmas plumose. 

Spikes slender, usually naked at the base or with a few scattered spikelets. 

Midnerve of the third scale not pilose, but hispidulous above the middle. 1. C NcaWyi, 

Nerves of the third scale all pilose. 

Apex of the elliptic fourth scale acute. 

Apex of the obovate-cuneate fourth scale obliquely truncate. 3. C\ verticillata. 

Spikes stout, spikelet-bearing to the base. 

Hairs on the nerves of the third scale short, 0.5 mm. long or less, not manifest, nor 
extending beyond the apex of the scale. 
Fourth scale obovate-cuneate, 3-nerved, 0.6 mm. wide, the apex unequally 

rounded. 
Fourth scale obcuneate or triangular, 5-nerved, 1 mm. broad or a little more. 5. C. la'ii-yuamea. 
Fourth scale broadly triangular, 7-nerved, wider than long. 6. C. cu ullata. 

Hairs on the lateral nerves of the third scale long, 1 mm. long or more, manifest 
and decidedly extending beyond the apex of the scale. 
Scales 6 : hairs on the lateral nerves of the third scale about equal in length. 
Hairs exceeding the apex of the scale, about 1 mm. long : fourth scale 1 mm. 

wide : upt»er surface of the leaves glabrous. 7. C. Tezana, 

Hairs much exceeding the apex of the scale, 2-3 mm. long: fourth scale 0.5 

mm. wide : uppersurface of the leaves near the base usually long-hairy. 8. C. harhata. 
Scales 7-9. the upper ones much reduced ; hairs on the lateral nerves of the 

third scale unequal in length, those at the summit much longer. 9. C. Prieuri. 

1- Chloris Nealleyi Nash. Stems 3-6 dm. tall : leaf-blades 2.5-15 cm. long, 3-5 
mm. wide, rough above : spikes 5-8, 10-18 cm. long : spikelets, exclusive of the awns, 
about 4 mm. long : scales 4 ; outer empty scales acuminate ; third scale, exclusive of the 
awn, 4 mm. long, in side view equilateral and 0.8 mm. wide, acute, the interneVves rough, 
the lateral nerves pilose above the middle, the awn 6-9 mm. long ; fourth scale 2-2.5 mm. 
long, in side view elliptic and about 0.5 mm. wide, the apex acute, the awn 4-5 mm. long. 

In dry soil, Texas. Summer. 

2, Chloris tenulspica Nash, Stems 2-4 dm. tall : leaf-blades 4-15 cm. long, 2-3 
mm. wide, abruptly acute, rough above and on the margins : axis of the inflorescence 2 
cm. long or less : spikes 10-12, 6-10 cm. long, spreading, very slender, in about 2 whorls: 
spikelets, exclusive of the awns, about 3 mm. long : scales 4 or 5 ; outer empty ones nar- 
row, acuminate, awn-pointed ; third scale about 3 mm. long, in side view elliptic and 0.7 
mm. wide, the nerves pilose, the awn 4-6 mm. long ; fourth scale nearly glabrous, smaller 
than the tliird, 1.75-2 mm. long, acute at the apex, the awn 2.5-4 mm. long; fifth scale 
smaller. 

In dry soil, Texas. Summer. 

3. Chloris verticillata Nutt. Stems 2-5 dm. tall : leaf-blades 1,5-18 cm. long, 2-4 
mm. broad, rough above and on the margins, obtuse: axis of the inflorescence 0.5-5 cm. 



long : spikes 8-21, spreading, 5-15 cm. long, in 1-4 whorls, or the upper ones scattered or 
approximate: spikelets, exclusive of the awns, about 3 mm. long : scales 4 ; outer emptpr 
ones acuminate, awn-pointed ; third scale 2.5-2.75 mm. long, in side view nearly equi- 
lateral and 0.8 mm. wide, the nerves pilose, the awn 5-8 mm. long ; fourth scale 1.5-2 mm. 
long, in side view obovate-cuneate and about 0.75 mm. wide, the apc»x obliquely truncate, 
-the awn 4-5 mm. long. 

In sandy soil, Arkansas to Kansas and Texas. Pummer. 



134 



POACEAE 



4. Chloris brevispica Nash. Stems 1-2 dm. tall : leaf-blades 1-6 cm. long, 1-3 mm. 
wide, rough above and on the margins : spikes 6-10, finally spreading, 2.5-4.5 cm. long : 
spikelets, exclusive of the awns, about 2.8 mm. long : scales 4 ; outer empty ones lanceo- 
late, acute ; third scale 2.5 mm. long, in side view elliptic and about 0.75 mm. wide, the 
nerves pilose, the hairs about 0.5 mm. long, the awn about 2 mm. long; fourtli scale 
obovate-cuneate, about 1.5 mm. long, in side view about O.C mm. wide, the apex unequally 
rounded, the awn 1.4-1.8 mm. long. 

In sandy soil, Texas. Summer. 

5. Chloris latisquamea Xash. Stems 2-6 dm. tall : leaf-blades 1-10 cm. long, 2-4 
mm. Avide, obtuse, rough : axis of the inflorescence 1.5 cm. long or less : spikes 10-16, 3-7 
cm. long, finally widely spreading: spikelets, exclusive of the awns, 2.3-2.8 mm. long: 
scales 4 ; outer empty ones acute ; third scale 2.2-2.7 mm. long, in side view elliptic and 
0.8-0.9 mm. Avlde, the nerves pilose, the awn 1.5-3 mm. long; fourtli scale 1.5-1.7 mm. 
long, in side view obcuneate or triangular and 1-1.2 mm. broad, 3-nerved, the lateral 
nerves much curved, branching at the middle, thus making the scale appear 5-nerved at 
the truncate apex, 0.5 mm. Avide, the awn 1.5-2 mm. long. 

In dry ground and on shady river banks, Texas. Summer. 

6. Chloris cucullata Bisch. Stems 2-7 dm. tall : leaf-blades 2-15 cm. long, 3 mm. 
wide or less, very rough : spikes 6-15, 2-4 cm. long, spreading : spikelets, exclusive of the 
awns, about 2 mm. long, triangular, about as broad as long : scales 4 ; fii-st scale acute, the 
second broader above the middle; third scale 1.7-2 mm. long, in side view elliptic and 
about 0,9 mm. wide, obtuse, the lateral nerves densely pilose with short hairs about 0.4 
mm. long, the midnerve sparingly so, the awn 0.5-1 ram. long ; fourth scale aboiU 1 mm. 
long, in side view broadly triangular and 1.3 mm. broad, the lateral nerves branching 
twice, making the scale appear 7-nerved above, the awn 0.2-0.3 mm. long. 

In sandy soil, Texas. Fall. 

7. Chloris Texana (Vasey) Nash. Stems 2.5-6 dm. tall : leaf -blades 6-20 cm. long, 
3-6 mm. wide, rough on the margins and toward the apex on the lower surface : spikes 
3-6, 4-8 cm. long : spikelets, exclusive of the awns, about 2.8 mm. long : scales ; outer 
empty ones very acute, pointed ; third scale about 2.7 mm. long, in side view inequilateral 
and 1 mm. broad, the. nerves pilose with hairs about 1 mm. long, the aAvn about 1.5 mm. 
long; fourth scale 1.7 mm. long, in side view obovate-cimeate and 1 mm. wide at the 
truncate and obscurely crenulate apex, 3-nerved, the awn 1-1.25 mm. long; fifth scale 1 
mm. long ; sixth scale about 0.5 mm. long. 

In low land, southern Texas. Summer. 

8. Chloris baibata (L. ) Nash, Stems 5-10 dm, tall : leaf-blades 6 dm. long or 
less, 1 cm. wide or less, attenuate into long slender tips, smootli : spikes 6-25, flexuous 
and spreading, 5-15 cm. long : spikelets, exclusive of the awns, about 3 mm. long : scales 
6 ; outer empty ones acuminate ; third scale about 2.25 mm. long, in side view elliptic and 
about 0-75 mm. wide, the nerves pilose, the midnerve-hairs about 0.5 mm. long, the re- 
mainder of irregular length, 2-3 mm. long, the awn 3-4 mm. long ; fourth scale about 1.3 
mm. long, in side view obovate-elliptic and about 0.5 mm. wide, obliquely truncate at the 
crenulate apex, the awn 2.5-3 mm. long ; fifth and sixth scales smaller. 

In sand or moist places, southern peninsular Florida! Also in the West Indies and South America. 
Summer. 

9. Chloris Prieuri Kunth. Stems 4-10 dm. tall : leaf-blades 1.5 dm. long or less, 3-6 
mm. wide, rough above and on the margins : spikes 4-15, 6-9 cm, long, erect : spikelets, 
exclusive of the awns, about 4 mm. long : scales 7-9, the upper ones nnich reduced; outer 
empty scales acuminate, awn-pointed ; third scale, exclusive of the awn, 3-3.5 mm. long, 
in side view narrowly oblong and about 0.5 mm. wide, acute, a row of dark glands on each 
side of the glabrous midnerve, the lateral nerves glabrous below the middle, pilose above, 
the awn 8-13 mm. long, the palet gland-bearing betAveen the nerves. 

Introduced at Wilmington, North Carolina, and on ballast at Mobile, Alabama. Summer. 



79. EUSTACHYS Desv. 

Perennial grasses, with flat or folded usually obtuse leaf-blades and spicate inflores- 
cence, tlie spikes single, in pairs, or 3-many and digitate. Spikelets usnally 1-flowered, 
rarely 2-flowered, if the latter the upper flower staminate, sessile, crowded in 2 rows.. 
Scales 4, rarely 5, the 2 lower empty, pemstent, unequal, keeled, the fii-st generally acute, 
the second oblong, truncate or 2-lobed at the apex, short-awned, the remaining scales awn* 



less, mucronate, or short-awned, firmer than the empty scales, the third scale enclosing A 
perfect flower and a palet^ the fourth scale empty, or rarely enclosing a staminate flower, 



POACEAE 



135 



the fifth scale, when present, empty, similar in texture to the fourth. Stamens 3. Styles 
distinct. Stigmas plumose. 

Spikelets 2 mm. lung : third and fourth scales awnless, or the former sometimes with 
a mere dorsal projection. 
Spikes usually 4-6, rarely more: second scale of the'spikelet manifestly 2-toothed 

at the apex : leaf-blades usually 3-7 mm. wide. 1, E. peiraen. 

Spikes 10-25: second scale of the spikelet truncate at the apex: leaf-blades usu- 
ally 1 cm. wide or more. 
Spikelets 3 mm. long or more : third and fourth scales awned. 

Spikes usually 1 or 2, rarely 3 : third scale of the spikelet over 3 mm. long. 3. E, Floridanu. 

Spikes 4-6 : third scale of the spikelet less than 3 mm. long. 4, E. ncglccta. 



1. Eustachys petra&a (Sw. ) Desv. Stems 3-11 dm. tall: leaf-hlades 3 dm. long or 



2. E. glattca. 




third scale about 2 mm. long, in side view elliptic and about 1 mm. wide, tlie nerve-hair.^ 
about 0.3 mm. lou^, the awri short or wanting ; fourth scale 1.3-1.5 mm. long, in side view 
obovate-elliptic, 0.5-0.7 mm. wide, rounded at the apex, awnless. \_Cfilo7Hs pdraea Sw,"] 

In dry sandy soil, usually along the coast. North Carolina to Florida and Texas, Also in tropica) 
America. In Florida it occurs in the heart of the peninsula, 50 miles from the coast. Summer. 

2. ^Eustachys glauca Chapm. Stems 6-15 dm. tall : leaf -blades 2.5 dm. long or less, 
1.5 cm. wide or less, smooth : axis of the inflorescence 2.5 cm. long or less : spikes 10-25, 
0-15 cm. long : spikelets about 2 mm. long : scales 4 ; second scale, exclusive of the awn, 
1.5 mm. long, in side view about 0.3 mm. wide, minutely and irregularly toothed at the 
truncate apex, the awn about 0.3 mm. long; third scale 1.75-2 mm. long, in side view 
ovate and 0.8-0.9 mm. wide, obtuse at the awnless apex, the nerves hispid above the 
middle ; fourth scale about 1.3 mm, long, in side view oblong and about 0.5 mm. wide, 
rounded-truncate at the awnless apex. [^Chloris glauca (Chapm.) Yasey.] 

In brackish marshes and about cypress swamps, Florida. Summer. 

3. Eustachys Florldkna Chapm. Stems 4-10 dm. tall : leaf-blades smooth, the 
early basal ones 1-3 dm. long, 4-8 mm. wide, those on the stem 2-7 cm. long, 5 mm. wide 
or less : spikes 1-3, erect, 5-10 cm. long : spikelets, exclusive of the awns, 3-3,5 mm. long : 
scales 4, the second about 2.5 mm. long, exclusive of the awn, unequally 2-lobed at the 
apex, the lobes rounded and minutely and irregularly toothed, the awn 0.7-1 mm. long ; 
third scale 3-3.5 mm. long, in side view elliptic and 1-1,2 mm. wide, the nerve-hairs about 
0.5 mm. long, the awn 0,5-0.7 mm. long; fourth scale smaller, the awn less than 0.5 mm. 
long. [^Chloris Floridana (Chapm.) Vasey.] 

In dry sandy soil, southern Georgia and northern Florida. Summer, 

4. Eustachys negl6cta Nash. Stems 7-12 dm. tall : leaf-blades 2 dm. long or 
less, 9 mm. wide or less, smooth : vSpikes 4-6, erect, 8-15 cm. long : spikelets, exclusive of 
the awns, about 3 mm, long : scales 4, rarely 5 ; second scale, exclusive of the awn, about 
2.5 mm. long, 2-lobed at the apex, the lobes obtuse and minutely and irregularly toothed, 
the awn about 1 mm. long ; third scale 2.5-2.8 mm. long, in side view about 1 mm. wide, 
the nerve-hairs about 0.7 mm. long, the awn 1 mm. long ; fourth scale 1.5-2 mm. long, in 
side view obovate-elliptic, about 0.75 mm. wide, the awn less than 1 nnn. long ; fifth scale 
smaller. 

In dry sandj' soil, eastern and peninsular Florida. Summer. 

80. TRICHLORIS Fourn. 
Tall grasses, with flat leaf-blades and usually numerous slender spikes which are closely 
approximate or snbverticillate. Spikelets sessile, densely crowded in 2 rows on one side of 
the continuous rachis, 1-, rarely 2-3-flowered, the rachilla extending beyond the flowers as 



a scale-bearing appendage. Scales usually 3, sometimes more, the 2 outer empty, small, 
persistent, membranous, the first usually very narrow, acute, awnless, the second short- 
awned, the flowering scale or scales 3-awned, the awns long and nearly equal or the lateral 
much shorter, the remaining scales empty or sometimes reduced to mere awns ; palet hya- 
line, 2-keeled near the margins. Stamens 3. Styles distinct. Stigmas plumose. 

1. Trlchlorls pluriflora Fourn. Stems erect, 4-12 dm. tall : leaf-blades flat, 3 dm. 
long or less, 5-10 mm. wide: spikes 5 or more, 5-15 cm, long, slender: spikelets, exclu- 
sive of the aAvns, about 4 ram. long, the awn of the flowering scales 2-3 times their length. 

In dry soil, central and western Texas. Also in Mexico. Spring and summer. 

81. GYMNOPOGON Beauv. 
Usually perennial grasses, with flat, generally short, rarely long, leaf-blades and an in- 
florescence composed of numerous long slender spikes which are alternately arranged or 



136 



POACEAE 



the lower ones snbverticillnte. Spikelets l-flowered, narrow^ sessile or nearly so, scattered^ 
appressed, the rachilla glabrous and prolonged beyond the flower, bearing at its apex a 
small usually awned scale. Scales 4, the 2 lower empty, persistent; narrow, acute, or the 
second short-awned, the third scale somcAvhat broader, shortly 2-toothed at the apex, bear- 
ing a straight awn, and enclosing a narrow 2-keeledpalet and a perfect flower ; fourth scale 
empty, awned, the body often much reduced. Stamens 3. Styles distinct. Stigmas plu- 
mose. 

Spikes spikelet-bearing their whole lengrth : awn longer than the flowering scale. 1. G. amhiquus. 

Spikes spikelet-bearing only above the middle: awn shorter than the flowering scale. 2. G. brevifolius. 

1, Gymnopogon ambiguus (Miclix.) B.S.P. Stems 3-5 dm. tall, erect, or decum- 
bent at the base : leaf-slieaths with a villous ring at the summit, crowded at the base of the 
stem; blades 2-10 cm. long, 4-12 mm. wide, lanceolate, crowded at the base, spreading: 
spikes slender, the lower ones finally widely spreading, 1-2 dm. long : spikelets, exclusive 
of the awn, 4-5 mm. long, the awn of the flowering scale 4-6 mm. long. [Gr. racemosus 
Beauv, ] 

In dry sandy soil, southern Xew Jersey to Mis^^ouri, Florida and Texas. Summer and fall. 

2. Gymnopogon brevifolius Trin. Stems 3-0 dm. long, decumbent at the base, 
slender ; leaf -sheaths sometimes crowded at the middle of the stem ; blades 2-5 cm. long, 
2-8 ram. wide, lanceolate, usually spreading : spikes very slender, the lower one^ finally 
widely spreading and 1-1.5 dm. long: spikelets, exclusive of the awn, 3 mm. long, the 
flowering scale short-awned. 

In dry soil, New Jersey to Florida and Mississippi. Summer and fall. 

82. SCHEDONNARDUS Steud. 

Annual grasses, with narrow almost subulate leaf-blades and an inflorescence consisting 
of numerous long slender spikes arranged in an open panicle. Spikelets l-flowered, acumi- 



nate, scattered, appressed, sessile and alternate on opposite sides of tlie rachis. Scales 3, 

membranous, the 2 lower empty, persistent, nari'ow, acuminate, somewhat unequal, the 

third scale longer, at length rigid, enclosing a narrow shorter palet and a perfect flower. 

Stamens 3. Styles distinct. Stigmas plumose. 

1. Schedonnardus paniculatus (Nutt. ) Trulease. Stems 2-5 dm. tall, slender, erect, 
rigid, branched at tlie base: leaf-slieaths crowded at the base of the stem, compressed; 
blades 2-5 cm. long, 2 mm. wide or less, usually erect, flat : spikes numerous, widely spread- 
ing, alternate, rigid, the lower ones 5-10 cm. long : spikelets 2.5-3 mm. long, appressed, 
alternate. 

In dry soil, Manitoba and Assiniboia to Illinois, Texas and New Mexico. Summer and fall. 

83. BOUTELOTJA Lag. 

Annual or perennial grasses, with narrow flat or convolute leaf-blades, and an inflores- 
cence composed of few scattered one-sided, often more or less curved, many-flowered sessile 
spikes with the rachis sometimes conspicuously prolonged beyond the spikelets. Spikelets 
numerous, 1-2-flowered, the lower flovver perfect, the upper one when present staminate or 
sterile, crowded in 2 rows. Scales 3 or more, the 2 lower empty, narrow, acute, un- 
equal, keeled, the third one enclosing a narrow hyaline palet and a perfect flower, usually 
thinner and broader, 3-nerved, the nerves excurrent from the lobes or teeth as short pro- 
jections or awns or protruding between the lobes, the small empty scales terminating the 

rachilla 1-3, 3-awned. Stamens 3. Styles distinct. Stigmas plumose. MesquiteGbass. 

Awns terminating the lobes of the flowering scale. 
Stems glabrous. 

Rachilla of the spikelet with a dense tuft of long hairs at the apex. 1. B. oligosfachya. 

Rachilla glabrous. 

Second empty scale \\'ith large hair-bearing tubercles on one or both sides 

of the midnerve. 2. B. hirsuta. 

Second empty scale glabrous and free of tubercles. 

Flowering" scale pubescent with long ascending silky hairs. 3. B. Barkci. 

Flowering scale glabrous, or sometimes with a few hairs at the base. 4. B. tvijida. 

Stems densely villous below. 5. B. eriopoda, 

Awns arising between the lobes of the flowering scale. 6. B. ndcrostacht/s. 

1. Boutelona oligostAchya (Nutt.) Torr. Stems 1.5-5 dm. tall, erect : leaf-blades 
2-10 cm. long, 2 mm. wide or less, involute, at least at the long slender point : spikes 1-3, 
2.5-5 cm. long, the rachis ending in a short inconspicuous tip : spikelets about 6 mm. long, 
the rachilla with a tuft of long hairs under the rudimentary scales and awns. 

On prairies, Manitoba to Alberta, Wisconsin and Texas. Also in Mexico. Summer and fall. 



i 



POACEAE 



137 



2. Bouteloua hirsuta Lag. vStems erect, 1.5-5 dm. tall: leaf-blades mostly at tlie 
base of the stem, 2-13 cm. long, 2 mm. wide or less, erect or ascending, flat, rough, spar- 
ingly papillose-hirsute near the base, especially on the margins : spikes 1-4, 1-5 cm. long, 
erect or ascending, the rachis extending beyond the spikelet in a conspicuoiis point : 
spikelets 5-() mm. long. 

In dry soil, especially on prairies, Illinois to North Dakota, Texas and Arizona, and in southern 
peninsular Florida. Summer aud fall. 

3. Bouteloua Biirkei Scribn. Perennial. Stems tufted, 3 dm. tall or less: leaf- 
blades spreading, often involute, l-o cm. long, about 1 mm. wide, stiff': spikes 3-6, erect, 
1-2 em. long : spikelets diverging from the rachis, about 2.5 mm. long, excbisive of the 
asvns. 

In dry soil, central and western Texas. Also in Mexico. Spring and summer. 

4. Bouteloua trifida Thurb. Perennial. Stems tufted, 3 dm. high or less : leaf- 
blades spreading, often involute, 4 dm. long or less, about 1 mm. wide : spikes 3-G, erect, 
1.5-3 em. long : spikelets diverging from the racliis, 3-4 mm. long, exclusive of the aAvns. 

In dry soil, central Texas to New Mexico. Also in Mexico. Spring and summer. 

5. Bouteloua eriopoda Torr. Perennial. Stems tufted, 3-6 dm. tall, at least the 
lower internodes densely villous : leaf-blades 1.5 dm. long or less, 1-2 mm. Avide, usually 
attenuated into a long slender point, erect : spikes 2-5, erect, 2-5 em. long : spikelets di- 
verging from the rachis, 6-8 mm. long, exclusive of the aAvns. 

In dry soil, central Texas to Arizona. Summer and fall. 

6. Bouteloua microstachys Fourn. Annual. Stems tufted, erect or ascending, 
slender, 1-3 dm. tall, sometimes branching : leaf-blades spreading or ascending, flat, 1-7 
cm. long, 1-2 mm. wide: spikes 2-7, usually curved, ascending, 1.5-3 cm. long : spikelets 
diverging from the rachis, 2-3 mm. long, exclusive of the awns, the flowering scale 
strongly pubescent, the rachilla with a terminal tuft of hairs. 

In dry soil, southern Texas to southern California. Also in Mexico. Summer and fall. 

84. ATHEROPOGON Muhl. 

Perennial grasses, w^ith narrow flat leaf -blades and an inflorescence composed of numer- 
ous scattered short few-flowered spikes. Spikelets 1-flowered, sessile, crowded in 2 rows, 
imbricated, the rachilla extending beyond the flower, its summit bearing scales or awns. 
Scales 3 or more, the 2 lower empty, unequal, narrow, acute, keeled, the third scale thin- 
ner and broader, 3-toothed at the apex, the teeth more or less awned, enclosing a narrow 
hyaline 2-toothed palet and a perfect flower, the small upper scales empty, awned. Stamens 
3. Styles distinct. Stigmas plumose. 

1. Atheropogon curtip6tiduius (Michx.) Fourn. Stems 3-9 dm. tall, tufted : leaf- 
blades 5-30 cm. long, 4 nmi. wide or less, flat or involute, rough : spikes 6-16 mm. long 
widely spreading or reflexed : spikelets 4-12, diverging from the rachis, 7-10 mm. long. 

[_IioiUeloua racemosa Lag.] 

In dry soil, Ontario to Manitoba, New Jersey. Kentucky, Georgia (according to Feay and Chap- 
man) and Texas. Also in Mexico. Summer and fall. 

85. TRIATHERA Desv. 

Annual or perennial grasses, with flat or involute leaf -blades and slender panicles com- 
posed of short slender one-sided spikes. Spikelets narrow, appressed, the rachilla terminat- 
ing in 3 stout awns. Scales 3, long-acuminate, tlie 2 outer empty, unequal, the flowering 
scale 3-toothed at the ai)ex, the teeth usually awned. Stamens 3. Styles distinct. Stig- 
mas plumose. 

1. Triathera aristidoides (H.B.K.) Nash. Stems slender, 1-4 dm. tall, wiry, finally 
somewhat branched : leaf-blades 2-10 cm. long, 1-2 mm. wide, flat, or sometimes involute : 
panicle slender, 4-10 cm. long, consisting of 5-20 spreading spikes 1-1.5 cm. long, their 
bases strongly appressed-pubescent with long silky hairs : spikelets 2-3 in each spike. 

In dry places, central Texas to southern California. Also in Mexico. Summer and fall. 

86. POLYODON II.B.K. 

Perennial grasses, with flat or Involute leaf-blades, and short spikes arranged in slender 
panicles. Spikelets l-flowered, appearing clustered by reason of the very short internodes 
of the rachis. Scales 5 or 6 : the 2 outer empty, narrow, acuminate ; third scale 3-awned, 



> 



enclosing a jierfect flower; remaining scales empty, the lower 3-awned, the uppermost usually 
reduced to 1-3 awns. SUxmens 3. Styles 2, slender, distinct, distantly inserted. Stigmas 
plu 




138 



POACEAE 



1. Polyodon Tex^nus (S. Wats.) Xaslu Ptems tufted, wiry, erect, slender, 1-4 dm. 
tall ; leaf-blades 2 dm. lon^ or less, 1-2 mm. wide, often involute: panicle 3-6 cm. long^ 
of 5-8 shoi't spreading spikes which are 9-12 mm. long : spikelets 2-4 in each spike. 
[^Bouteloua Texana S. Wats.] 

In dry soil, the Indian Territory and Texas. Spring and summer. 

87. ELEUSINB Gaertn. 
\nnual, or perennial and creeping, grasses, with flat leaf-blades, and an inflorescence 



composed of normally several spikes arranged digitately or approximately with sometimes 
an additional single spike below. Spikelets numerous, much crowded, imbricated, sessile, 
alternate in 2 rows, several-flowered, the flowers perfect, or the upper ones staminate. 
Scales several, obtuse or acute, flattened, keeled, thin, the 2 lower empty, a little shorter 
than the others, the remaining scales usually more obtuse, each of the lower ones enclosing 
a scarcely shorter compressed 2-keeled palet and a flower, the terminal scales empty. Sta- 
mens 3. Styles distinct. Stigmas plumose. 

1. Eleusine Indica (L. ) Gaertn. Stems 1.5-6 dm. tall, erect, or decumbent at the 
base ; leaf -sheaths loose, overlapping, often short and crowded at the base of the stem ; 
blades 7-30 cm. long, 2-6 mm. wide : spikes 2-10, whorled, or approximate at the summit 
of the stem, or sometimes with 1 or 2 distant ones, 2-8 cm. long : spikelets 3-4 mm. long, 
3-6-flowered. 

In waste places, fields and dooryards nearly throughout North America. Naturalized from the 
Old World. Summer and fall. "Wire CtKass. Yard Grass. Crab GitASs, Dog Grass. Crow-foot. 

88. DACTYLOCTENIUM AVilld. 

Annual grasses, with flat leaf-blades and an inflorescence consisting of one-sided spikes 
terminally arranged in pairs or digitate. Spikelets numerous, crowded, imbricated, ses- 
sile, alternate in 2 rows, several-flowered, the flowers perfect or the upper ones staminate. 
Scales several, acute and mucronate-i^ointed, or the second awned, thin, flattened, keeled, 
the 2 lower empty, the remaining scales broader, each of the lower ones enclosing a 
scarcely shorter compressed 2-keeled palet and a flower, the upper scales empty. Stamens 
3. Styles distinct. Stigmas plumose. 

1. Dactyloctenium Aegyptium (L. ) Willd. Stems 1.5-6 dm. tall, usually decum- 
bent and extensively creeping at the base : leaf-sheatlis loose, overlapping, often crowded ; 
blades 1.5 dm. long or less, 2-6 mm. wide, ciliate toward the base : spikes in pairs, or 3-5 
and digitate, 1-5 cm. long : spikelets 3-5-flowered. [Eleusine Aeyyptia Pers.] 

In cultivated ground and waste places, southern New York, Pennsylvania and Virginia to Illinois, 
California and Florida. Also widely distributed in tropical America. Naturalized from Asia or Africa. 
Summer and fall. Egyptian Grass. 

89. LEPTOCHLOA Beauv. 

Often tall grasses, with flat or convolute leaf-blades, and an inflorescence consisting of 
very many long slender spikes arranged in a panicle, rarely approximate at the summit of 
the stem. Spikelets small, close, or rarely scattered, 2-several-flow^ered, rarely 1-flowered, 
flattened, sessile, alternate in 2 rows. Scales 3-several, keeled, obtuse, acute, or shortly 
awned, the 2 lower empty, a little unequal, usually shorter than the spikelet, or in the 
1-flowered spikelets exceeding the third scale, the remaining scales more obtuse or some- 
times bearing a slender awn, each of the lower enclosing a prominently 2-keeled palet and 
a flower, the upper empty. Stamens 3. Styles distinct. Stigmas plumose. 

Spikes very slender, 1 mm. broad or less : empty scales generally about the same 
length, the first from nearly equalling to exceeding the first flowering scale. 
Flowering scales 1.5 mm. long, the pubescence on the nerves long and copious. 1. L, miicronata. 
Flowering scales less than 1 mm. long, the pubescence on the nerves short and 
scant. 
Spikes stouter, 2 mm. wide or more : empty scales usually very uneqiial, the first 
much shorter than the first flowering scale. 
Inflorescence generally loose and open, the branches elongated and more or less 
spreading, usually in whorls or sometimes opposite or alternate. 
Upper surface of the leaf-blades glabrous : scales of the spikelet usually 7-8, 
the flowering ones awnless, or sometimes the first and rarely the second 
short-awned- 
Upper surface of the leaf-blades hirsute toward the base : scales of the spike- 
let usually 5-6, the flowering ones all awned, the awn of the first more 
than }4 sii long as the body. 
Inflorescence long and narrow, the branches commonly short, erect or nearly 
so, crowded and disposed in dense alternate fascicles. 



2, L. attentiata. 



3. L, virgdta. 



4. L. DomingensU, 



POACEAE 



139 



Sheaths smooth or nearly so : flowering scales 1.75 mm. long, broad, obtuse, 

the nerves densely pilose excepting at the summit. 5. L. NealleyL 

Sheaths very rough : flowering scales 2.5 mm. long, narrow, acute, the nerves 

pilose below the middle. 6, L. scabra. 

1. Leptochloa mucronata (Miclix. ) Kunth. Stems 3-12 dm. tall, iinally branching : 
leaf-sheaths, at least tlie lower ones, generally more or less hirsute ; blades 6-25 cm. long, 
1 cm. wide or less, rough : inflorescence 1.5-5 dm. long, usually included at the biise : 
spikes slender, commonly elongated, ascending, 5-15 cm. long: spikelets 2.5-3 mn). long ; 
scales usually 5 ; the 2 outer empty, acute, equal, or the first somewdiat shorter than the sec- 
ond, the first commonly a little shorter than the first fiowering scale, rarely somewhat ex- 
ceeding it ; flowering scales about 1.5 mm. long, rounded at theemarginate apex, the 
pilose, excepting at the apex, the hairs copious and long. 

In fields, Virginia to Florida and California. Summer. 

2. Leptochloa attenuata Xutt. Stems tufted, 2-0 dm. tall, finally branching : leaf- 
sheaths more or less hirsute ; blades 4-20 cm. long, 3-8 mm. wide, rougli, sparingly hir- 
sute above; inflorescence L5-2 dm. long, usually included at the base : sj)ikes slender, 
spreading or ascending, 4-10 cm. long : spikelets 1.6-2 mm. long : scales 5 or t> ; the 2 outer 
empty, subulate, acuminate, awn-pointed, generally about equal, or the first shorter than 
the second which reaches the apex of the second flowering scale ; flowering scales a little 
less than 1 mm. long, rounded at the apex, the nerve-hairs scant and very short. 

In low sandy bottoms, Illinois to the Indian Territory. Fall. 

3. Leptochloa virgata (L. ) Beauv. Stems 2-10 dm. tall: leaf-sheaths glabrous; 
blades 5-30 cm. long, 5-15 mm, wide, often rough above : inflorescence 1-2.5 dm. long, 
exserted : spikes numerous, erect or ascending, usually in whorls, sometimes scattered or 
in pairs, 3-12 cm. long, rather stout: spikelets 3.5-4 ram. long : scales G-9 ; the 2 outer 
empty, broad, acute; flowering scales 2-2.5 mm. long, the midnerve glabrous, sometimes 
excurrent in a short point or awn, the lateral nerves pubescent for the upper two-thirds. 

In sandy soil, Texas. Also in Mexico, South America and the West Indies. Summer. 

4. Leptochloa Doming6nsis (Jacq. ) Trin. Stems 2-10 dm. tall, finally branching : 
leaf-sheaths glabrous or sparingly hirsute ; bhides 1-3 dm. long, 1 cm. wide or less, some- 
times rough beneath, hirsute above: inflorescence 1-2 dm. long, its axis smooth: spikes 
erect or somewhat ascending, usually numerous, the lower ones 3-10 cm. long : spikelets, 
exclusive of the awns, 2-3 mm. long : scales 4 or 5 ; the 2 outer empty unequal, acute, 
shorter than the spikelet ; flowering scales 1.75-2.25 mm. long, acute, internerves glabrous or 
appressed-pubescent, the lateral nerves pilose for part w'ay above the middle, the midnerve 
hispidulous above the middle and extending into an awn i to fully as long as the body. 

In sand, peninsular Florida and southern Texas. Also in tropical America. Summer. 

5. Leptochloa Nealleyi Vasey. Stems 4-10 dm. tall : leaf-sheaths smootli and gla- 
brous ; blades 4-20 cm. long, 2-4 mm. wide, roughish ; inflorescence 1.5-3.5 dm. long, in- 
cluded at the base : spikes very numerous, short and stout, 2-5 cm. long, appressed : spike- 
lets crowded, about 3 mm. long : scales 5 or 6 ; the 2 outer empty, broad, obtuse, the first 
about 2 as long as the second which is ^ as long as the spikelet or less ; flowering scales 1.75 
mm. long, rounded at the apex, the midnerve sometimes excurrent, the nerves pilose, ex- 
cepting at the apex, with long hairs. 

In low land, central and southern Texas. Summer. 

6. Leptochloa scabra Nees. Rough throughout. Stems 1 m. tall or less : leaf- 
sheaths glabrous ; blades 2-4 dm. long, 1 cm. wide or less : inflorescence 2-4 dm. long, in- 
cluded at the base : spikes very numerous, erect-ascending, sometimes curved, tlie lower 
ones 5-8 cm. long : spikelets 3.5-4 mm. long : scales usually 6 ; the 2 outer empty, acute, 
the first ^ as long as the second which is less than i as lon^ as the spikelet ; flowering scales 
about 2.5 mm. long, acute, the nerves pilose below the middle, the midnerve also hispidu- 
lous above the middle and usually excurrent in a short awn. 

In ditches and fields, Louisiana. Probably introduced. Fall. 

90. ACAMPTOCLADOS Xash. 

Perennial tufted grasses, with stiff stems, flat or involute leaf-blades and a panicle 
composed of scattered and distant widely spreading rigid branches. Spikelets scattered 
and distinct, singly disposed in two rows, sessile, 4-6-flowered. Scales 6-8, firm : the 2 
, lower empty, acuminate, about equal, the first 1-nerved, the second usually 3-nerved ; 
flowering scales very acute, becoming harder in fruit, 3-nerved, the nerves glabrous, the 
lateral nerves vanishing at the margin below the apex ; palet compressed, its 2 nerves cilio- 
late, gibbous at the base. Stamens 3. Styles distinct. Stigmas plumose. 



140 



POACEAE 



1. Aoamptoclados sessilispicus (Buckl. ) Nash, vStems 2-1-4 dm. tall, erect, sim- 
ple : leaf-sheaths crowded at the base of the stem, hahy at the summit ; blades 5-15 era. 
long, 1.5-3 mm. wide, rough above : panicle 1-4 dm. long, its branches stout and rigid: 
spikelets 4-6-flowered, the flowering scales 4 mm, long. \_Eragrosiis sessilispica Buckl. J 

On prairies, Kansas to Texas. Summer and fall. 

91. BULBILIS Eaf. 

Perennial creeping stoloniferous grasses, Avith narrow flat leaf-blades and the inflores- 
cence of two forms, one stamlnate, consisting of one-sided spikes approximate at the sum- 
mit of long-exserted stems, the other pistillate, on short stems, composed of small spike- 
like clusters barely exserted from the sheath. Spikelets dioecious, sessile, very unlike. 



Staminate spikelets 2-3-flowered, crowded in 2 rows on one side of the short flattened 
spikes; scales 4 or 5, membranous; stamens 3. Pistillate spikelets 1 -flowered, the larger 
scales united at the base and involucre-like ; scales 3, the 2 outer empty, the first mem- 
branous, usually small, sometimes simiUir to the second which is the largest, firm, concave 
at the base, 3-lobed at the apex, the flowering scale narrow, nearly hyaline, enclosing a 
broad convolute 2-nerved palet and a flower. Styles distinct, long. Stigmas elongated, 
short-plumose. 

1. Bulbilis dactyloides (Nutt.) Raf. Stoloniferous. Stamiqate stems 1-3 dm. tall, 
erect, slender, naked above : pistillate stems 1-8 cm. long, much exceeded by tlie leaves : 
leaf-blades 2 mm. wide or less, papillose-hirsute, those on the staminate stems 2-10 cm. 
\of\g^ erect, those on the stolons and pistillate stems 2.5 cm. long or less and spreading : 
staminate spikes 2 or 3, approximate, the 2-3-flowered spikelets 4-5 ram. long, flattened : 
pistillate spikelets ovoid, the outer scales indurated. 

On plains and prairies, Minnesota to North Dakota, Arkansas and Texas. Also in Mexico. Sum- 
mer. Buffalo Grass. 

92. PAPPOPHORUM Schreb. 

Perennial tufted grasses, with narrow leaf-blades and dense spike-like panicles. Spike- 
lets usually 1-2-flowered, narrow. Scales usually 4-6 ; the 2 lower empty, acute, carinate ; 
flowering scales firm, divided into many awn-like lobes. Stamens 3. Styles short, distinct. 



Stigmas plumose. 

1. Pappophorum ap6rtuni Munro. Stems tufted, 5-10 dm. tall, erect, rather stiff", 
finally somewluit branched : leaf-sheaths pubescent at the summit on the outside ; blades 
o dm. long or less, usually involute: panicle 1-2 dm. long, narrow, its branches erect: 
i^pikelets 7-8 mm. long, including the awns, the flowering scales pubescent on the margins 
and keel for h their length. 

In dry soil, central Texas to Ari;iona, Also in Mexico. Spring and summer. 



*■ 



93. MONANTHOCHLOE Engelm. 

Perennial creeping or stoloniferous monoecious grasses, with short rigid convolute often 
curved leaf-blades crowded at the nodes, and an inconspicuous inflorescence concealed 
among the leave=». Spikelets unisexual, the staminate hardly differing from the pistillate, 
2-flowered, rarely 3-flowered, usually sessile and in pairs, or stipitate and single, in the leaf 
fascicle-i, the rachilla continuous and prolonged beyond the flower and sometimes bearing a 
short terminal scale. Scales 4 or 5, the 2 outer empty, somewhat resembling the floral 
leaves, dLstichous, membranous and sheathing at the base, linear, rigid and spreading 
above, many-nerved, the remaining scales membranous, firndy hyaline, obtuse or denticu- 



late, enclosing a 2-nerved convolute palet and a flower. Stamens 3. Styles distinct, long, 
tigmas elongated, shortly barbellate-plumose. 



1. Monanttiochloe littoralis Engelm. Branches densely tufted from creeping stems, 
1-5 dm. tall, stiff, wiry: leaf-blades crowded on short branches, widely spreading, 1.5 cm. 
long or less, stiff, often curved. 

In sand along the seacoast, southern Florida and southern Texas and Lower California. Sprin^^ 
and summer. 

94. MUNROA Torr. 

Low annual tufted grasses, with many rigid and often creeping dichotomously or fascic- 
ulately ))ranched stem, short rigid spinescent leaves which are crowded at the nodes or at 



rOACEAE 



141 



the summit of the branches, and an inconspicuous inflorescence which is almost concealed 
in the leaf-fascicles. Spikelets feu*, usually 3-flowered, almost sessile, in small clusters in 
the axils of the floral leaves. Scales several, the 2 outer empty, persistent, narrow, acute, 
hyaline, nerveless, the remaining ones 3-nerved, larger, entire, rctuse, or 3-cleft at the 
apex, tlie central nerve or all of them excurrent in a short tip, each of tlie lower scales 
enclosing a narrow folded hyaline 2-keeled palet and a perfect flower, the upper scales 
empty, similar to the flowering ones but smaller and narrower or sotnetinies with one re- 
duced to 3 awns. Stamens 3. Styles elongated. Stigmas loosely and shortly plumose. 

1. Munroa squarrosa (Xutt. ) Torr. Stems 5-20 dm. long, tufted, erect to prostrate, 
much branched : leaf-sheaths sliort, crowded at the nodes and ends of the branches ; bL'ulee 
2.5 cm. long or less, 1-2 mm. Avide, rigid, spreading, rough, pungently pointed : spikelets 
2-5-flowered ; flowering scales 3-tootlied, the teeth short-pointed or awned. 

On dry plains, South Dakota to Alberta, Nebraska, Texas and Arizona. Summer and fall. 

95. ARUNDO L. 

Tall perennial grasses, with thick stout somewhat woody stems, broad flat leaf-blades 

and dense panicles. Si:)ikelets 2-many-flowered, the rachilla-internodes glabrous. Scales 

4-many ; empty scales narrow ; flowering scales broader, 3-nerved, hairy on the back. 

Stamens 3. Styles distinct. Stigmas plumose. 

1. Arundo Donax L. Stems stout, erect, 3-6 m. tall : leaf-blades often 5 (hn. long 
or more and sometimes 4-5 cm, wide : panicle 5-8 dm. long, oblong : spikelets numerous, 
crowded. 

Occasionally escaped from cultivation in the southern United States. Native of the tropical and 
warmer regions of }x)ih hemispheres. Summer, 

96. PHRAGMITES Trin. 

Tall perennial graases, with flat usually broad leaf-blades and ample terminal panicles. 
Spikelets 2-several-flowered, the lower flower staminate, the remainder perfect, tlie rachilla 
articulated between the flowers and covered with long silky hairs which surround the fertile 
scales. Scales 4-several, glabrous, thin, narrow, acute, keeled, the 2 outer empty, the first 
much shorter than the second, the remaining scales long-acuminate, the lowest one enclos- 
ing a staminate flower, the remainder of the scales narrower and each containing a perfect 
floAver or the upper sometimes empty ; palet hyaline, much shorter than the scale, 2-keeled. 
Stamens 3. Styles distinct, short. Stigmas plumose. 

1. Phragmites Phragmites (L. ) Karst. Stems 1-5 dm. tall, stout, erect, from long 

rootstocks : leaf -sheaths loose, overlapping ; blades 1.5-3 dm. long or more, 1-5 cm. wide, 

flat: panicle ample, 1.5-3 dm. long or more, its branches ascending: spikelets crowded, 

the floAvering scales 10-12 mm. long, long-acuminate. [P. communis Trin.] 

In swamps and wet places in almost all parts of North America north of Mexico. Also in Enroj.c* 
and Asia. Summer and fall. Common Reed. 

97. TRIDENS R. & S. 

Usually perennial grasses, with flat or involute leaf-blades and the inflorescence com- 
posed of open or contracted and sometimes spike-like panicles. Spikelets 3-many-flowered, 
the flowers perfect or the upper ones staminate. Scales 5-many, membranous, sometimes 
firmer, the 2 low^er empty, keeled, obtuse to acuminate, usually shorter than the rest, some- 
times longer: floAvering scales 3-nerved, the midnerve or all the nerves excurrent, the 
midnerve and the lateral nerves or the margins pilose, the apex entire or shortly 2-toothed, 
the teeth obtuse to acute, the callus short and obtuse ; palet shorter than the scale, com- 
pressed, 2-keeled. Stamens 3. Styles short, distinct. Stigmas plumose, 

A. Panicle open, the branches long and more or less spreadm^. 

Lateral nerves of the flowering scale vanishing at the margin, not excurrent. 
Spikelets 4-5 mm. long, the nerves of the palet not abruptly gibbous below 

the middle. 
Spikelets S-10 mm. long, nerves of the palet abruptly and strongly gibbous 

below the middle. 
Lateral nerves manifestly excurrent in short projections. 
Spikelets oval, more than }^ as broad as long 

Spikelets 7-9-flowered, 5 mm. long : palet rounded at the decidedly apic- 

ulate apex, the nerves ciliolate, the internerve broadly ovate-oval. 3. T. amUginis, 
Spikelets 4-6-fiowered, 6-7 mm. long : palet obtuse at the apex, the nerves 

ciliate, the internerve elliptic or nearly so. 4. T. Langlmm, 

Spikelets elliptic to linear-oblong, less than % as broad as long. 6. T. $€$leriouiff. 



1. T, eragrostoidfif, 

2. T. Texanm. 



142 



POACEAE 



8. T. congcdus. 

9. T, muticus. 



B. Panicle narrow, often spike-like, its branches erect or apy)ressed. 
Second empty scale 1-nerved. 

Lateral nerves excurrent in short projections, the nerve^hairs less than 1 
mm. long. 

Panicle exceeding 1.5 dm. in length : spikelots not turgid, the palet- 

nerves not gibbous at the base, 
i Sheaths, at least the basal, villous ; spikelets l<x)sely arranged, the 

empty scales broad, %_ as long as tlie spikelet or less. 6. 7. Drummo7idiL 

Sheaths glabrous: spikelets crowded, the emjtty scales narrow and 

often equalling or exceeding the flowering scales. 7. T, strktas. 

Panicle less than 1 dm. long: spikelets turgid, the palet-iierves abruptly 
and strongly gibtous at the base. 
Lateral nerves of the flowering scale vanishing below the aj)ex : nerve-hairs 
about 1.5 mm. long. 
Second empty scale 3-5-nerved. 

Spikelets 8-10-flowered, 10-14 mm. long, the hairs on tlie margins and mid- 
nerve of the flowering scales copious. 10. T. elongatus. 
Spikelets 3-5-rtowered, h-S mm. long, the hairs on the margins and midnerve 

of the flowering scales scanty. 11. T. liuckleyanus, 

1. Tridens eragrostoides (Vitsey i.S: Scribn.) Xasli. Stems tufted, o-12 dm. tall, 
smooth : leaf-sheaths overlapping, rough ; blades erect or ascending, 2-3 dm. long, 4-7 
mm. wide, long-acuminate, rough : panicle loose and open, 1.5-3 dm. long, its rough 
branches ascending, the larger 3-12 cm. long: spikelets loosely arninged, 7-10-flowered, 
4-5 mm. long, 2.5 mm. broad, ovate ; empty scales 1-ncrved, ueuniinate, hispid on the 
keel, the first much narrower than the second ; flowering scales about 2.5 mm. long, oval 
and about 1.5 mm. wide when spread out, the n[)ex rounded or nearly truncate, denticulate, 
the hairs on their margins and midnerve about 0.2 mm. long, the midnerve usually excur- 
rent, the lateral nerves vanishing at the margin. [IVwdia erafjrodokles Yii^ey & Scvihn.^ 

On hillsides, southern Florida and Texas. Also in Mexico. Summer and fall. 

2. Tridens Texknus (Thurb. ) Nash. Stems tufted, 2-7 dm. tall, more or less hirsute 
toward the base : stem-leaves 2 or 3 ; sheaths glabrous to sparingly hii-sute, pilose at the 
summit ; blades 3 dm. long or less, 2-4 mm. wide, long-acuminate, often more or less hir- 
sute : panicle loose and open, 6-17 cm. long, its branches at length spreading, tlie lower 
2-7 cm. long: spikelets loosely disposed, 8-11 -flowered, 8-10 mm. hmg, obU)ng to narroAvly 
ovate; empty scales rather bri>ad, 1-nerved, acute; flowering scales about 3.5 mm. long, 
oval and about 2.5 mm. brond when spread out, thd apex obtuseh^ 2-toothed, their nerve- 
hairs about 0.7 mm. long, the lateral nerves barely if at all excurrent, the midnerve shortly 
so ; palet with the ciliolate nerves gibbons below tlie middle. {_Triodla Texana Thurb.] 

On hills and in valleys, TiOuisiana to Arizona and northern Mexico. Summer. 

3. Tridens ambiguus ( Kll. ) Schult. Stems 5-0 dm. tall, smooth : leaf-sheaths smooth 
and glabrous; blades 0.5-3 dm. long, 1-3 mm. wide : panicle loose and open, 8-^20 cm. long, 
its branches ascending, the larger 4-10 cm. long : spikelets loosely arranged, 7-9-flowered, 



about 5 mm. long, 2.5-3 mm. wide, oval ; empty scales rather broad, acute, 1-nerved ; 
flowering scales 3-3.5 mm. long, oval and about 2 mm. broad Avhen spread out, their 
nerve-hairs about 0.7 mm. long, the lateral nerves slightly excurrent, and the midnerve in 
an awn about 0.3 mm. long ; palet ciliolate on the nerves, the internerve broadly ovate- 
oval, the roxmded apex decidedly apiculate. \_TrbHUa amblgaa (KU. ) Vasey.] 

In dry pine lands, South Carolina to Florida. Summer and fall, 

4. Tridens Langloisii Nash. Stems 5-15 dm. tall, smootli : leaf -sheaths glabrous, or 
pilose at the summit ; blades minutely pubescent above, the basal 2-4 dm. long, 2.5-5 mm. 
wide, those on the stem shorter and narrower : panicle narrow, 1-2 dm. long, about 2 cm. 
broad, its branches erect or neiirly so, the larger 6-10 cm. long : spikelets loosely arranged, 
4-6-flowered, 6-7 mm. long, 3-4 mm. wide ; empty scales rather broad, acute, l-nerved or 
the second rarely 3-nerved ; tlo\Vering scales about 4 mm. long, elliptic and 2.25 mm. wide 
when spread out, their nerve- hairs about 0.5 mm. long, the apex minutely 2-toothed, the 
nerves excurrent in short tips ; palet ciliate on the nerves, tne apex obtuse, the inter- 
nerve elliptic or elliptic-ovate. 

In pine lands, western Florida to Texas. Summer and fall. 

5. Tridens seslerioides (Michx. ) Nash. Stems tufted, 5-16 dm. tall, smooth: 
stem-leaves 2-6 ; sheaths smooth, villous at the summit, those at the base crowded, the 
remainder shorter than the internodes ; blades elongated, the basiil and lower ones 2-6 dm. 
long, 5-15 mm, wide, the uppermost one 6-20 cm. long, long-acuminate, smooth ; panicle 
loose and open, 1.5-4 dm. long, its branches from nearly erect to spreading, drooping at 
the end, the lower from 7-25 cm. long, the axils more or less villous : spikelets usually 
numerous, 5-8-flowered, 7-10 mm. long, elliptic to linear-oblong ; empty scales rather 
broad, acute, 1-nerved ; flowering scales about 4 mm. long, their nerve-hairs about 0.7 mm. 
long, the apex 2-toothed between the excurrent nerves. [^Triodia cuprea Jacq. ] 

In drvsoil, New York to Illinois. Kansas, Florida and Texas. Summer and fall.— T'. seslerioides 
nKipmdnit iSma.U) Nash, differs from the species in its smaller panicle with more rigid branches and 
more densely villous axils, and in the more acute teeth of the flowering scale. It occurs in Georgia, and 
from Texas to Oklahoma and the Indian Territory. Rki>-toi'. 



J 



POACEAE 



143 



6. Tridens Drummoudii (Scribn. & Kearn. ) Nash. Stems 8-12 dm. tall from a 

scaly rootstock, smooth : basiil leaf-sheaths crowded, villous, the upper ones glabrous or 

nearly so ; blades of the basal leaves elongated, 2-4 dm. long, about 5 ram. wide ; blade 

of the uppermost stem-leaf 3 cm. long or less : panicle narrow, spike-like, 1.5-2 dm. long, 

its branches short and appressed : spikelets rather loosely arranged, 3-5-flowered, 8-10 

mm. long; empty scales broad, 1-nerved, short-awned at the shortly 2-toothed apex; 

flowering scales firm, 5-6 mm. long, elliptic-ovate when spread out, their nerve-hairs about 

0.8 mm. long, the apex 2-lobed, the nerves excurrent as projections. [IV iodia Drummoudii 
Scribn. & Kearn.] 

In dry soil or in low pine lands, South Carolina to Mississippi and Florida. Fall. 

7. Tridens str Ictus (Nutt.) Nash. Stems 5-15 dm. tall, smooth : leaf-sheaths smooth ; 
blades erect or ascending, 4 dm, long or less, 2-7 mm. M'ide, long-acuminate, smooth ex- 
cept on the margins: panicle narrow, spike-like, 1.5-3 dm. long, 1-1.5 cm. broad, its 
branches short and appressed : spikelets crowded, C-lO-flowered, 5-6 mm. long ; empty 
scales narrow, 1-nerved, acuminate, usually exceeding the flowering scales ; flowering 
scales 3.5-4 mm. long, 1.5 mm. broad and elliptic when spread out, their nerve-hairs about 
0.8 mm. long, the lateral nerves usually slightly excurrent, the midnerve extended into a 
short awn 0.25-0.5 mm. long. [Triodia stricta (Xutt. ) Vasey.] 

In moist soil and meadows, Kansas to Mississippi and Texas. Summer and fall. 

8. Tridens cong^stus (L. 11. Dewey) Nash. Stems tufted, 1-7 dm. tall, smooth : 
leaf-sheaths shorter than the internodes, smooth ; blades ascending, 5-20 cm. long, 2-5 
mm. wide, long-acuminate, smootli beneath, roughish above : panicle dense, 3-8 cm. long, 
1-1.5 cm. broad, its branches short and erect: spikelets nearly sessile, crowded, turgid, 
8-15-flowered, 8-12 mm. long, about 4 mm. broad, ovate to oblong ; empty scales broad, 
1-nerved, acute ; flowering scales about 5 mm. long, orbicular wlien spread out, tlieir nerve- 
hairs about 0.8 mm. long, the midnerve and often also the lateral nerves excurrent in short 
projections; palet-nerves hispid and saccate at the base. \_Triodia conyesta L. H. Dewey.] 

'*' In dry soil, Texas. Spring to fall. 

9. Tridens muticus (Torr. ) Nash, Stems tufted, 2-5 dm. tall, roughened: leaf- 
sheaths glabrous or papillose-hirsute ; blades erect or ascending, 2-12 cm. long, 3 mm. 
wide or less, often involute when dry, rough : panicle narrow, 6-15 cm. long, its branches 
appressed : spikelets 6-9-flowered, 10-12 mm. long, lanceolate ; empty scales 1-nerved ; 
flowering scales 4-5 mm. long, obscurely and irregularly lobed at the obtuse or rounded 
apex, the hairs on their margins and midnerve about 1.5 nnn. long, the lateral nerves 
vanishing below the apex, the midnerve also, or the latter continued to the apex, or rarely 
excurrent as a short projection. [Tricui<pis mittica Torn] 

On dry hills, Texas to Arizona and northern Mexico. Spring to fall. 

10. Tridens elong^tiis (Buckl. ) Nash. Stems tufted, 3-9 dm. tall, very rough : leaf- 
sheaths longer than the internodes, rongh ; blades erect or ascending, 4-25 cm. long, 3 mm. 
broad or less, long-acuminate, rough : panicle narrow, 12-25 cm. long, its branches ap- 
pressed : spikelets 8-10-flowered, 10-14 mm. long, 3-4 mm. wide, elliptic; first empty 
scale 1-nerved, the second 3-5-nerved ; flowering scales 5-6 mm. long, the apex obtuse or 
minutely 2-toothed, their hairs on the margins and midnerve about 1 mm. long, the lateral 
nerves vanishing below the apex, the midnerve excurrent as a short projection. 

On plains or prairies, Colorado to Texas and Arizona. Summer and fall. 

11. Tridens Buckleyinus (Vasey) Xash. Stems 6-8 dm. tall, very rough, as are 
the sheaths: leaf-blades 0.5-2 dm, long, 1-2.5 mm. M'ide, involute when dry, rough on 
both surfaces: panicle narrow, slender, 1.5-2.5 dm. long, its main axis and appressed 
branches rough, the larger ones 3-5 cm. long : spikelets loosely disposed, 3-5-flowered, 5-8 
mm. long, 1.5-2 mm. wide, narrowly elliptic ; empty scales narrow, acuminate, the first 



1-nerved, the second 3-nerved ; flowering scales about 5 mm. long, elliptic and about 2 mm. 
wide when spread out, the apex minutely 2-toothed, the midnerve sometimes excurrent in 
a ghort tip between the teeth, the lateral nerves vanishing just below the apex, the hairs on 
the margins and midnerve scanty, about 0.4 mm. long. [Triodia Buckkyana Vasey.] 

In dry soil, southern Texas. Summer and fall. 

98. ERIONEURON Xash. 

Perennial tufted grasses, with thick linear leaf-blades having thickened white mar- 
gins, and dense contracted almost capitate panicles. Spikelets several-many-flowered : 

4 



broad 



base 



144 



rOACEAE 



1, T. purpurea. 



white hairs, the apex acuminate, entire or slightly 2-tootlie(l, tlie awn terniinal or arising 
between the minute teeth. Stamens 3. Styles short, distinct. 

1. Erloneuron pilosum (Buckl.) Nash. Stems densely tufted, 0.4-3 dm. tall, naked 
above : leaf-sheaths sparingly pilose at the summit ; blades erect, folded, linear, obtuse or 
abruptly acutish at the apex, thick, with broad white serrulate margins, papillose-hirsute, 
especially beneath, the basal numerous, 2-8 cm. long, those on the stem usually 3 cm. 
long or less : panicle racemose or nearly so, 1-3 cm. long: spikelets 3-8, crowded, 1-1.5 
cm. long, about 5 mm. broad, the empty scales acuminate, 1-nerved, the flowering scales, 
exclusive of the awn, o.5-C mm. long, acuminate, entire or slightly toothed at the apex, 
the internerves pilose at the base, the nerves pilose on the lower 4 and the midnerve 
also above the middle, the longer hairs about 2 mm. long, the awn 1-1.5 mm. long. 

In dry gravelly soil, Kansas and Colorado to Texas and Arizona. Summer. 

99. TRIPLASIS Beauv. 

Perennial grasses, with very narrow flat or convolute leaf-blades and terminal con- 
tracted or open somewhat branched panicles. Spikelets shortly pedicellate, 2-6-flowered, 
the flowers perfect or the upper staminate, the glabrous rachilla articulated between the 
flowers, the internodes long. Scales 4-8, membranous, the 2 lower empty, keeled, acute 
shorter than the rest, the flowering scales distant on the rachilla, dorsally rounded at the 
base, 3-nerved, the lateral nerves pilose, deeply 2-lobed at the apex, the lobes obtuse, acute 
or acuminate, each with a glabrous or pubescent awn arising between the lobes, the callus 
long and subulate ; palet shorter than the scale^ compressed, 2-keeled, the keels long-ciliate. 
Stamens 3. Styles short, distinct. Stigmas plumose. 

Flowering scale % as broad as long or more, with a shorter straight awn 3 mm. long 
or less. 

Lobes of the flowering scale rounded or truncate at the irregularly and minutely 
toothed a^>ex ; awn less than 2 mm. long. 

Lobes of the flowering scale acute or acutish at the apex ; awn 2.5-3 mm. long. 2. 71 'intermedia 

Flowering scale i/.^ as broad as loiig, its lobes acuminate, pointed, the awn longer 

than the scale, 6 mm. in length or more, recurved, at least when dry. 3. 7. Araericana. 

X. Triplasis purpurea (Walt.) Chapm. Stems tufted, 2-8 dm. tall: leaf-sheaths 
rough; blades 15 cm. long or less, 1-3 mm. wide, rcmgh : panicle finally exserted, its 
branches in I's or 2's, 4 cm. long or less : spikelets on short hispidulous pedicels: scales 
4 or 5 ; the 2 onter empty, acuminate ; flowering scales about 4 mm. long, 1.75 mm. wide 
when spread out, divided about \ way dow n, the lobes rounded or truncate at the irregularly 
and minutely toothed apex, the awn equalling or a little exceeding the lobes, pilose on the 
lower half, less than 2 mm. long, straight. [jP. sparsiflora Chapm.] 

In sandy soil, usually along the coast, Ontario to Florida and Texas. Also along the Great I^akes 
and from Missouri and Nebraska southward. Summer. Sand Grass. 

i 

2. Triplasis Intermedia Nash. Stems densely tufted, 4-8 dm. tall, slender: leaf- 
sheaths very rough, papillose-hirsute toward the base wdth long ascending hairs ; blades 
13 cm. long or less, involute when dry, rough, hirsute above : panicle finally exserted, its 
branches in l's-3^s, pubescent at the base, rough, the larger ones 2-4 cm. long : spikelets on 
short pubescent pedicels, 8-10 mm. long ; scales 5 or 6 ; the 2 outer empty, acuminate ; 
flowering scales 4.5 mm. long and 1,5 mm. w^ide Avhen spread out, divided from J-^ their 
length, the lobes acute to somew^hat obtuse, the awn 2.5-3 mm. long, straight, much exceed- 
ing the scale. 

In dry sandy soil, southern peninsular Florida. Summer. 

3. Triplasis Americana Beauv. Stems tufted, 3-8 dm. tall, slender, puberulent : 
leaf-sheaths smooth ; blades 15 cm. long or less, less than 2 mm. wide, smooth, the upper 
surface minutely pubescent : panicle finally exserted, its branches single or in pairs, 3 cm, 
long or less : spikelets on short hispidulous pedicels ; scales 4 or 5 ; the 2 outer em})ty, 
acuminate ; flowering scales about 5 mm. long and 1 mm. broad when spread out, divided to 
the middle, the lobes subulate, acuminate, pointed, the awn much exceeding the scale, usu- 
ally reflexed, at least when dry, pilose for about | its length, 6-8 mm. long. 

In dry sandy soil along the coast, North Carolina to Florida and Texas. Summer. 

100. REDFIELDIA Vasey. 

Tall perennial graases, with long narrow leaf -blades and a terminal ample diffuse pan- 
icle, its branches long and capillary. Spikelets numerous, 1-3-flowered, theflow^ers perfect. 
Scales 3-5, acute, the 2 outer empty, about equal in length, the remaining scales com- 
pressed-keeled, larger, each furnished with a basal ring of hairs, 3-nerved, the middle 



POACEAE 



145 



nerve often excurrent as a short tip ; palet shorter than tlie scale, 2-nerved. Stamens 3. 
Styles long, distinct. Stigmas short, plumose. 

1. Redfieldia flexuosa (Thurb. ) Vasey. Stems 1 m. tall or less, from a stout rootstoek : 
leaf-blades elongated, 2-6 dm. long, 2-4 nmi. wide, smooth : panicle loose and open, 1.5-5 
dm. long, its branches spreading or ascending, the larger 7-15 cm. long, their divisions 
spreading and more or less flexuons : spikelets 5-6 mm. long, on slender spreading pedicels ; 
scales 4-7; the 2 outer empty, acuminate; flowering scales 5-6 mm. long, acuminate, the 
callus densely pilose with long hairs. 

On prairies, Nebraska and Wyoming to the Indian Territory and Colorado. Summer and fall. 

101. DIPLACHNE Beauv. 

Tufted often tall gnisses, with narrow flat leaf-blades and an inflorescence usually com- 
posed of numerous long slender spikes or racemes (rarely reduced to one and terminal), 
racemosely arranged on a long axis. Spikelets linear, sessile or nearly so, often scattered 
along and appressed to the rachis, many-flowered, the floAvers perfect or the upper ones 
staminate. Scales many, membranous, the 2 lower empty, persistent, keeled, acute, un- 
equal, the remaining scales larger, the apex often 2-toothed and mucronate or short-awned 
between the teeth ; palet shorter than the scale, hyaline, 2-nerved or 2-kceled. Stamens 
3. Styles distinct. Stigmas plumose. 

Inflorescence of a single raceme. 1. />. spicata. 

Inflorescence of 5-many racemes. 

Flowering scales entire or shortly and acutely 2-toothed at the apex, usually 
awned or awn-tipped. 
Palet pilose on the infolded margins. 

Awn less than J^ as long as the body of the flowering scale. 

Spikelets 4-8 "mm. long, the flowering scales acute or obtuse at the 2- 

toothed apex, the lateral nerves often excurrent. 2. D. fasdeiikuii*. 

Spikelets 10-12 mm. long, the flowering scales acuminate at the usually 

entire apex, the lateral nerves rarely excurrent. 3. 7X acuminata. 

Awn % as long as the body of the flowering scale or more. 4. />. procuinhtns. 

Palet not pilose on the infolded margins. 5. D, Jlalci, 

Flowering scales usually awnless, 2-toothed at the apex, the teeth broad and 

rounded. 6. B. dubia, 

1. Diplachne spickta Doell. Stems densely tufted, 1-2 dm. tall, naked above, twice 
as long as the innovations or more : leaf-sheatlis short, more or less pilose at the apex ; 
blades erect, sparingly pilose, 0.5 mm. wide, involute, those on the stem 3 cm. long or less, 
those on the innovations longer : inflorescence of ^a single raceme, 4-10 cm. long : spikelets 
7-8 mm. long ; scales 8-10, the lower empty ones rather narroAV, the flowering scales, ex- 
clusive of the awn, about 3 mm. long, the nerves glabrous, the lateral ones vanishing below 
the apex, the midnerve excurrent in an awn 0.75-1.5 mm. long, the apex 2-toothed, a tuft 
of long hairs on the rachilla at the base of the palet. 

Among rocks, central Texas to Mexico. Summer and fall. 

2. Diplachne fascicul^ris (Lam.) Beauv. Stems tufted, finally branched, 3-8 dm. 
tall, somewhat exceeding the innovations to twice their length : lower leaf-sheaths often 
rough ; blades erect, 1-2 dm. long, 3 ram. wide or less : involute Avhen dry, rough, the 
uppermost one often equalling or exceeding the inflorescence : inflorescence usually partially 
included at the base, its 8 or more racemes erect or erect-ascending, the larger^nes4-8cm. 
long: spikelets 6-8 mm. long; scales 10-12, the lower empty ones acute, the flowering 
scales, exclusive of the awn, 3-4 mm. long, the apex commonly 2-toothed, the nen^es pilose 
below the middle, the lateral nerves usually slightly excurrent, the midnerve extending 
into an awn 1 mm. long or less. 

Along the coast, Florida to Texas, and in the Mississippi Valley to Missouri. Summer and fall. 

3. Diplachne acuminata Nash. Stems tufted, 3-6 dm. tall, finally branched : leaf- 
sheaths rough at the summit ; blades erect, 1-3 dm. long, 4.5 mm. wide or less, usually 
involute w^hen dry, very rough, uppermost one generally exceeding the inflorescence : in- 
florescence partly included at the base, the exserted portion 2.5 dm. long or less, its 



branches and the main axis rough, the former erect or ascending, the larger 0.7-1,5 dm. 
long: spikelets 10-12 mm. long ; scales 8-11, the lower empty ones acuminate, the flower- 
ing scales 6-7 mm. long, acuminate at the entire or occasionally slightly 2-toothed apex, 
the lateral nerves rarely slightly excurrent, the midnerve extending into an awn 0.75-1.3 
mm. long, the lateral nerves pilose below the middle, the midnerve rarely slightly so at the 
base. 

In wet or moist soil, Nebraska and Colorado to Arkansas. Summer. 

4. Diplachne proctimbens (Muhl. ) Nash. Stems tufted, finally branched, 2-4 dm. 
tall : leaf-slieaths smooth ; blades erect, 8-20 cm. long, 4 mm. wide or less, involute when 

10 



146 



rOACEAK 



dry, the uppermost one mucli exceeding the inflorescence : inflorescence included at tlie 
base, the exserted portion 12 em. long or less, its brandies erect, the larger 5-7 cm. long : 
spikelets about 1 cm. long ; scales 8-10, the lower empty ones acuminate, usually awned or 
awn-pointed, the flowering scales, exclusive of the awn, 4.o-5 mm. long, acuminate at the 
2-toothed apex, the nerves pilose below the middle, the lateral ones usually slightly excur- 
rent, the awn ^ as long as the scale-body or more. [Leptochloa polysfachya Chapxn,'] 

In brackish marshes, New York to South Carolina. Suramer and fall. 

5. Diplachne Halei Xash. Stems 6-10 dm. tall, Anally branched: leaf-sheaths 
smooth ; blades erect or ascending, 1.5-4 dm, long, 6-12 mm. wide, flat, very rough : in- 
florescence finally exserted, 2-3 dm. long, 4-10 cm. wide, its numerous branches ascending, 
4-7 cm. long: spikelets 4-6 mm. long, about 2 mm. wide; scales 7-10, the lower empty 
ones rough, the first scale acute, the second obtuse, tlie flowering scales about 3 mm. long, 
slightly and usually obtusely 2-toothed at the obtuse apex, the lateral nerves pilose toward 
the base, not excurrent, the midnerve glabrous or pilose toward the hase, excurrent in an 
awn 0.2 mm. long or less. 

In marshes, Louisiana to Texas. Summer and fall. 

6. Diplachne dubia {II.B.K. ) Benth. Stems tufted, 3-10 dm. tall, simple: leaf- 
sheaths smooth ; blades erect, smooth or rough, 2-8 mm. wide, the uppermost one 1.5-8 
cm. long, the lower 1.5-4 dm. long: inflorescence usually finally exserted, 1-2 dm. long, 
the 5-20 racemes erect to spreading, the larger 5-11 cm. long : spikelets 5-9 mm, long ; 
scales 5-10, the lower empty ones acuminate, the flowering scales about 4.5 mm. long, ob- 
long, rough at the 2-lobed apex, the lobes rounded at the summit, the nerves glabrous, the 
lateral ones vanishing considerably below the apex of the lobes, the midnerve at the cleft 
or rarely extending into a sliort awn, the margins of the s(*ale pilose below the middle. 

In woods and rocky places, Florida to Texas, Arizona and Mexico. Summer and fall. 



102. RHOMBOLYTRUM Link. 



Perennial grasses, with usually flat leaf-blailes and a narrow contracted spike-like 
panicle. Spikelets numerous, several-flowered. Scales several ; 2 lower empty, 1 -nerved ; 
flowering scales broad, rounded at the summit, o-nerved, the nerves glabrous, the lateral 
3 disappearing below the margin, the midnerve at the margin or scmietimes* excurren 



as a short projection. Stainens 3. Styles short, distinct. Stigmas plumose. 

1. Rhombolytnim albescens (Mnnro) Nash. Stems 2-6 dm. tall : leaf -sheaths 
shorter than the internodes ; blades ascending, 0.5-2 dm. long, 2-5 mm. wide, smooth : 
panicle contracted, spike-like, 6-15 cm. long, 8-15 mm. broad, its branches short and 
appressed : spikelets 4.5-5 mm. long, about 2.5 mm. wide, oval ; scales 8-10, the 2 outer 
empty ones rather broad, 1 -nerved, the flowering scales about 3 mm. long, nearly orbicular 
when spread out, rounded at the erose and sometimes acuminately 2-toothed apex, 3- 
nerved, the nerves glabrous, the lateral ones vanishing below the margin, the midnerve at 
the margin or sometimes excurrent as a short projection. 

In dry gravelly soil, Texas to Arizona. Summer, 

103. ERAGROSTIS Beauv. 

Low or tall annual or perennial tufted rarely dioecious grasses, the stems sometimes 
prostrate or creeping, with flat or convolute leaf-blades and open or contracted panicles. 
Spikelets numerous, arranged singly or in fascicles, 2-many-flowered, the flowers perfect or 
unisexual. Scales 4-many, membranous, compressed, keeled, the 2 lower empty, unequal, 
the remaining scales larger, 3-nerved, obtuse or acute at the apex ; palet shorter than the 
scale, prominently 2-nerved or 2-keeled, often incurved and persistent on the rachilla after 
the fall of the scale. Stamens 2 or 3. Styles distinct, short. Stigmas plumose. 



1. A'. Fra?tkii\ 



A, Stems not creeping : flowers perfect. 

a. Palet of the spikelets glabrous on the keels or merely hispiduloiis. 

* Annuals. 

Spikelets 2-5-flowered. 

Pedicels and branches of the panicle short : stems usually branched 

above. 
Pedicels and branches of the diffuse panicle long and capillary : stems 
branched only at the base. 
Stems slender, rarely equalling 5 dm. in height : leaf-blades usually 

1.5 dm, long or less. 
Stems stout, 8-12 dm. tall : leaf-blades elongated, 4-G dm. long. 3. E, hfrsuta. 

Spikelets more than 5- flowered. 

Panicle narrow, elongated, 2.5-5 dm. long, its branches erect or nearly 
so: spikelets crowded. 



2. E, capillarii^. 



4. E. glomrraia. 



POACEAE 



147 



Panicle open, usually less than 2.5 dm. long, its branches spreading or ascending: spike- 
lets not crowded. 

Spikelets 1.5 nun. wide or less: palets remaining attached to the continuous rachis for 
some time after the flowering scales have fallen. 
Flowering scales thin, usually bright purplish, the lateral 

nerves faint or wanting : spikelets about 1 mm. wide. 5. F. pilosa. 

Flowering scales firm, usually dull purple or greeu, the lateral 

nerves very prominent : spikelets about 1.5 mm. wide. 6. JC. Purshii. 

Spikelets more than 2 mm. wide : palets falling with the flowering 

scales and the internodes of the rachis. 7. E. major. 

** Perennials. 

Spikelets scattered on long branches. 

Branches of the open panicle spreading or ascending, rather stiff. 

Lateral nerves of the flowering scales faint. S. E. Uigens. 

Lateral nerves of the flowering scale very prominent. 

Spikelets short-pedicelled, the pedicel 1 mm. long or less. 9. E. curtipcdlcdlala, 

Spikelets on pedicels which are often as long as or much ex- 
ceeding the spikelet. 
Pedicels usually less than twice as long as the spikelet. 
Margins of the flowering scales convex above the middle, 

the scales hence merely acute. 10. E. pectinaccu. 

Margins of the flowering scales straight or concave above 

the middle, the scales hence acuminate. 11. E. refracta. 

Pedicels many times longer than the spikelets. 12. E, ElUotUi. 

Branches of the narrow and elongated panicle long and flexuous, 

erect or nearly so. 13. E, trichodcs. 

Sfakelets crowded and clustered on short branches : 

Linear-lanceolate, 2 mm. Avide or less. 14. £". Hmplex, 

Oblong to oval, exceeding 3 mm. in width. 

Flowering scales 3-4 mm. long, acute, firm. 15. E, secundiflora. 

Flowering scales 5 mm. long, acuminate, thin and papery. 16. E, Bcyrichii. 

h. Palets of the spikelets beautifully and conspicuously ciliate with long 
hairs. 
Panicle contracted, spike-like, the branches short and appressed. 17. E. clliaria. 

Panicle open, its branches spreading, 18. E, plumosa. 

B. Stems creeping, rooting at the nodes. 

Flowering scales less than 2 mm. long, glabrous. 19. E, hypnoidfu. 

Flowering scales 3-4 mm. long, pubescent. 20. E, capitata. 

1 Eragroatls Prdnkii Steud. Stems 1.5-4 dm. tall, tufted, erect, often decumbent at 
the base, branching : leaf-blades 5-13 cm. long, 2-4 mm. wide, rough above : panicle 5-15 
cm. long, open, its branches ascending : spikelets ovate, 2-3 mm. long, 3-5-Howered, the 
flowering scales acute, the lower ones 1.5 mm. long, their lateral nerves obscure. 

In moist places, Connecticut to Minnesota, Mississippi, Louisiana and Kansas. Fall. 



2. XlragTOBtis capUlaria (L. ) Nees. Stems 2-5 dm. tall^ slender, erect, finally 
branching at the base : leaf-blades 7-25 cm. long, 2-4 mm. wide : panicle diffuse, 1-4 dm. 
long, its capillary branches spreading or ascending : spikelets ovate, 2-3 mm. long, 2-4- 
flowered, the flowering scales acute, 1.5 mm. long, their lateral nerves obscure. 

In dry places, Rhode Island and New York to Missouri, Georgia and Texas. Summer and falL 

3. Eragrostis hirsuta (Michx. ) Nash, Stems densely tufted, rather stout, 7-13 dm, 
tall : leaf-sheaths, at least the lower ones, strongly papillose-hispid, each with a tuft of hairs 
at the apex ; blades, the lower leaves, 4-6 dm. long, less than 1 cm. wide, long-acuminate, 
flat : panicle 5-8 dm, long, diffuse, its long branches finally widely spreading : spikelets 
3-5-flowered, 3-4 mm. long, the flowering scales 2-2.5 mm. long- 
In dry fields, thickets and woodlands, South Carolina to Florida, the Indian Territory and Texas. 

Summer and fall, 

4. Eragrostis glomerkta (Walt.) L, H. Dewey. Stems erect, rather stout, 2.5-8 



dm, tall : leaf-sheaths glabrous ; blades rough, 2 dm. long or less, less than 1 cm. wide, 
long-acuminate : panicle narrow, contracted, 1-5 dm. long, its branches erect or nearly so : 
spikelets 5-10-flowered, 2.5-3.5 mm. long, the flowering scales about 1 mm. long. [E. 

conf er ta Trin.] 

In damp or wet places, South Carolina to Florida, Louisiana, Arkansas and Texas. Also in Mexico. 
Summer and fall. 

5. Eragrostis pilosa (L.) Beauv. Stems tufted, 1.5-5 dm. tall, erect, slender, 
branched : leaf-blades 2-13 cm. long, 2 mm. wide or less : panicle 5-15 cm, long, it« 
branches finally spreading, often hairy in the axils : spikelets 5-1 2-flowered, 3-6 mm, long, 
about 1 mm. wide, the flowering scales acute, the lower ones 1,5 mm. long, thin, the lateral 
nerves faint or wanting. 

In cultivated ground or waste places, southern New England to Illinois, Kansas. Florida and 
Texas. Naturalized from Europe. Summer and fall. 



6. Eragrostis Piirshii Schrad. Stems 1.5-5 dm. tall, tufted, finally much-branched : 




In dry places, throughout the United States and extending into Ontario. Sunuuer and fall. 



148 



POACEAE 



7. Eragrostis mijor Host. Jll-scenteJ. Stems 1.5-G dm. tall, at first erect, finally 
decumbent and much branched : leaf-blades 5-18 cm. long, 2-6 mm. wide, Hat: panicle 
5-15 cm. long, its brandies spreading or ascending : spikelets 8-35-floAvered, 5-16 mm, 
long and about 3 mm. wide, flat, the flowering scales obtuse, 2-2.5 mm. long, the lateral 
nerves prominent. \_E. ineffastachya Link.] 

In cultivated and waste places, nearly throughout Xorth America. Naturalized from Europe. 
Summer and fall. Skunk Grass. 

8. Eragroatis lugens Xees. Stems tufted, slender, 2-3 dm. tall : leaf-sheaths, at 
least the lower ones, papillose-hirsute with long spreading hairs ; blades erect, papillose- 
hirsute with long spreading hairs, 3-9 cm. long, 1.5-3 mm. wide : panicle 1-2 dm. long, 
its branches long and ascending : spikelets 3-7-flowered, 3.5-4.5 mm. long, 1.3 mm. wide. 

In dry soil, southern peninsular Florida. Also in Mexico and South America. Spring and sumraer. 

9. Eragrostls curtipedicellata Buckl. Stems 1.5-9 dm. tall, erect, rigid : leaf- 
sheaths overlapping, pilose at the summit; blades 5-20 cm. long, 2-4 mm. wide, rough 
above : panicle 1-3 dm, long, the branches widely spreading : spikelets 5-12-flowered, 
3-6 mm. long, the flowering scales about 1.75 mm. long, the lateral nerves prominent. 

On prairies, Kansas to Texas. Summer and fall. 

10. Eragrostia pectinkcea (Michx. ) Steud. Stems 3-8 dm. tall, rigid : leaf-sheaths 
overlapping, glabrous or pubescent, the upper one often enclosing the base of the panicle ; 
blades 1-3 dm. long, 4-8 mm, wide, rough above ; panicle 1.5-6 dm. long, purple or 
purplish, its branches widely spreading or the lower ones reflexed, strongly bearded in the 
axils: spikelets 5-15-flowered, 3-8 mm. long, the flowering scales about 1,75 mm. long, 
their lateral nerves very prominent. 

In dry usually sterile soil, New Hampshire to South Dakota, Florida and Texas. Summer and fall, 

11. Eragrostls refrdcta (Muhl. ) Scribn. Stems 3-9 dm. tall, slender: leaf -sheaths 
overlapping, glabrous ; blades 1-3 dm. hmg, 2-4 mm. wide, rough above and villous to- 
ward the base : panicle 2-5 dm. long, its slender branches finally widely spreading, the 
axils often bearded : spikelets 6-25-flowered, 5-12 mm. long, the flowering scales acumi- 
nate, 1.5-2 mm. long, the lateral nerves prominent. [E. campestris Trin.] 

In moist soil, Delaware and Maryland to^Florida and Texas. Summer and fall. 

12. Eragrostls Ellidttii S. Wats. Stems tufted, firm, erect, 4-10 dm. tall : leaf- 
sheaths glabrous ; blades 4 dm. long or less, 3-5 mm. wide» smooth beneath, rough above, 
long-acuminate : panicle diffuse, 2-5 dm. long, its long slender branches finally widely 
spreading or ascending: spikelets 6-13-flowered, 5-10 mm. long, the flowering scales 
1.75-2 mm. long, the lateral nerves prominent. [E. nitida Ell.] 

In dry soil, South Carolina to Florida and Louisiana. Fall. 

13. Eragroatis triohodes (Nutt. ) Nash. Stems 6-12 dm. tall : leaf-sheaths overlap- 
ping, pilose at the throat; blades 1.6-7 dm. long, 2-4 mm. wide, attenuate into long 
slender tips : panicle 2-7 dm. long, narrow and elongated, the branches capillary, the lower 
axils sometimes bearded : spikelets usually pale, or sometimes purple-tinged, 3-iO-flowered, 
5-9 mm. long, the flowering scales acute, the lower ones 2.5-3 mm. long, their lateral nerves 
manifest. 

In dry sandy soil, Ohio and Illinois to Nebraska, Arkansas and Texas. Summer and fall. 

14. Eragroatis simplex Scribn. Stems densely tufted, ascending, 2-6 dm. tall, rather 
stiff : leaf-sheaths and blades usually spai^y pubescent, the latter erect or ascending, 
7-10 cm. long and 2-4 mm. wide : panicle 1-2 dm. long, its branches stiff and widely 
spreading, usually 2-4 cm. long: spikelets 12-40-flowered, 5-17 mm. long, 1.6-2 mm. 
wide. [E, Brownei Chapm., not Nees.] 

In waste places and in ditches, Florida. Summer and fall, 

15. Eragroatis secundiflora Presl. Stems tufted, 1-9 dm. tall: leaf -blades 3 dm. 
long or less, 2-4 mm. wide : panicle 4-15 cm. long, its branches short and erect : spikelets 
crowded and clustered, 12-20-flowered, 6-14 mm. long, 3-4 mm. wide. [-E. oxykpisToTT.I 

In sandy soil, Missouri and Kansas to Mississippi and Texas. Also in Mexico. Summer and fall. 

16. Eragrostls Beyrfcbii J. ^ G. Smith. Stems tufted, 1-5 dm. tall : leaf-blades 
2 dm. long or less, 1-2 mm. wide, involute when dry : panicle 3-20 cm. long, its branches 
short and erect : spikelets crowded and clustered, 12-42-flowered, usually 1-2 cm. long and 
about 5 mm. wide, the flowering scales about 4 mm. long, acuminate, in side view cuneate. 

In sandy places, Texas. Also in Mexico. Summer. 

17. Eragrostls ciMris (L.) Link. Annual. Stems densely tufted, erector ascend- 
ing, slender, 1.5-4 dm, tall, often branching: leaf-sheaths usually ciliate on the margin 
and with a tuft of long hairs at the apex ; blades flat, ascending, 2-8 cm. long, 2-4 ram. 
wide : panicle spike-like, often interrupted below, 3-10 cm. long, its branches short and 



POACEAE 



149 



^. 



ap[)ressed : spikelets 6-16-flowered, the nerves of the palet long-ciliatC; the haii-s exceeding 
0-5 mm. in length. 

In waste places and cultivated ground, Georgia and Florida to Mississippi. Widely distributed in 
tropical America. Summer and fall. 

18. Eragrostis plumosa Link, Annual. Stems densely tufted, ascending, slender, 
1-4 dm. tall : leaf-sheaths usually ciliate on the margin and with a tuft of hairs at the apex ; 
blades flat, spreading or ascending, 2-10 cm. long, 2-4 mm. wide : panicle open, usually 
diffuse, oblong, 4-16 cm. long, its branches spreading or ascending : spikelets 4-8-fIowereu, 
the nerves of the palet ciliate with hairs about 0.2 mm. long. 

In cultivated ground and waste places, southern Georgia and Florida. Widely distributed in 
ti-opical regions. Spring to fall. 

19. Eragrostis hypnoidea (Lam.) B.S.P. Stems 2-5 dm. long, slender, creeping 
and rooting at the nodes, branched : leaf-blades pubescent above, sometimes also below, 
erect to spreading, commonly 1-4 cm. long, 1-2 mm. wide, flat, or sometimes involute : 
panicle 1.5-5 cm. long: spikelets 10-35-flowered, 4-16 mm. long, the flowering scales 1.5-2 
mm. long, glabrous, those of the pistillate spikelets more sharply acute than those of the 
staminate. \_E. reptans Nees.] 

Along shores, usually in sand or gravel, Vermont and Ontario to Oregon, Florida and Texas. Also 
in tropical America. Summer and fall. 

20. Eragrostis capit^ta (Nutt.) Nash. Stems branching and creeping, rooting at 
tlie nodes wliich send up branches 6-10 cm. long ; leaf -sheaths, at leJist those on the 
branches, pubescent: blades spreading or ascending, 1-3 cm. long, 1.5-3 mm. wide, flat, 
lanceolate, pubescent : panicle 2-3 cm. long, nearly or quite as broad, oval : spikelets 
crowded, clustered, 12-30-flowered, 6-14 mm. long. IFoa mpUata Nutt.] 

In sandy, usually wet soil, Arkansas and Louisiana to Nebraska, New Mexico and Texas. Also in 
Mexico. Summer. 

104. BATONIA Raf. 

Tufted j)erennial grasses, with flat or convolute leaf-blades and usually narrow and 
contracted, or sometimes open panicles. Spikelets numerous, 2-3-flowered, shining. Socklfes 
4 or 5, membranous, the 2 outer empty, the first very narrow, 1-nerved, acuminate, the 
second much broader, obovate when spread out, obtuse, truncate, and sometimes apiculate 
at the apex, 3-nerved, the remaining scales narrower, obtuse or somewhat acute ; palet 
narrow, 2-nerved. Stamens 3, Styles distinct, short. Stigmas plumose. 

Empty scales usually unequal, the lirst commonly shorter and not more than 1/5 
as wide as the second. 
Second scale obovate in side view, rounded at the summit. 

Leaf-sheaths, blades and stems glabrous. 1. E, obfusata. 

Leaf-sheaths, and often the blades and stems softly pubescent. 2. E. pubeacens. 

Second scale oblanceolate in side view, acute or acutish at the apex. 

Basal leaf-blades long, slender, involute, at least when dry, usually equal- 
ling or sometimes exceeding the stems. 3. E.fillformis. 
Basal leaf-blades short, broad, flat, many times shorter than the steins. 
Spikelets 3-3.5 mm. long. 
Spikelets 4-5 mm. long. 
Empty scales usually equal, the first at least }4 ^s broad as the second. 
Leaf-sheatlis and blades softly pubescent. 
Leaf-sheaths and blades glabrous. 

1. Eatonta obtuakta (Michx. ) A. Gray. Stems 3-8 dm. tall, often stout: leaf- 
sheaths and blades usually rough, the latter flat, 2.5-23 cm. long, 1-5 mm. wide, rarely 
wider : panicle 5-15 cm. long, dense and usually spike-like, strict, sometimes purple, its 



4. E. Pcnnsylvanica, 

5. E, Umgiflora, 

6. E, nitida. 

7. E, glabra. 



branches erect : spikelets crowded, 2.5-3 mm. long. 

In dry soil, Massachusetts and Ontario to Assiniboia, Florida and Arizona. Summer. 

2. Eatonia pub6scens Scribn. & Mer. A tufted perennial, with the leaf-sheaths, 
back of the ligule and lower part of the stem softly and densely pubescent. Stems 3-8 dm. 
tall : leaf -blades 5-18 cm. long, 3-6 mm. wide, glabrous, or often softly pubescent : panicle 
5-20 cm. long : spikelets 2.5-3.5 mm. long. 

In dr>' soil, Pennsylvania to Georgia and Texas. Spring and summer, 

3. Eatonia filifdrmis (Chapm. ) Vasey. Stems densely tufted, slender, 2.5-8 dm. 
tall : leaf-blades narrow, slender, involute, at least when dry, the stem-blades 2, usually 
less than 6 cm. long : panicle 6-12 cm. long, slender, often nodding at the apex : spike- 
lets 3.5-4 mm. long. 

In dry soil, South Carolina and Tennessee to Florida and Texas. Spring, 

4. Eatonia PennsylvAnica (DC.) A. Gray. Stems 3-9 dm. tall: leaf-blades 6-18 
cm. long, 2-6 mm. wide, rough : panicle 7-18 cm. long, often nodding at the summit, lax : 
spikelets 3-3.5 mm. long, the flowering scales narrow, acute. 

In hilly woods or moist soil, New Brunswick to British Columbia, Georgia and Texas. Summer. 



150 



rOACEAE 




5. Eatonia loagiflora (Vasey) Beal. Stems tufted, stout, 6-10 dm. tall: leaf-blades 
rough, lax, 5-20 cm. long, 4-8 mm. wide : panicle loose, lax, nodding at the apex, 1-2.5 
dm. long, its branches long, slender and erect : spikelets 4-5 mm. long. 

In dry soil, Louisiana and Texas. Spring. 

6. Eatonia nitida (Spreng. ) Nash. Stems tufted, slender, 3-6 dm, tall: leaf- 
sheaths pubescent ; blades 1-8 cm. long, 2 mm. wide or less, usually pubescent : panick 
6-15 cm. long, lax, its branches spreading at flowering time, finally erect : spikelets 3 mm. 
long. \_E. Dadlcyl Vasey.] 

In dry woods, Connecticut to Ontario, Georgia and Alabama. Spring and summer. 

7. Eatonia glabra Nasli. Stems densely tufted, slender, 3-7 dm. tall : leaf-sheaths 
labrous ; blades rough, flat, 2-7 cm. long, 1.5-3 mm. wide : panicle 7-15 cm. long, slen- 
er, nodding at the summit : spikelets 3-4 mm. long. 

In woods, southern Xcw York to Tennessee. Spring and summer. 

105. KOELERIA Pei^. 

Annual or perennial tufted grasses, with narrow flat or involute leaf-bhides and usu- 
ally dense contracted or spike-like cylindric, rarely elongated and interrupted panicles. 
Spikelets numerous, crowded, 2-5-flowered3 the flowers perfect or the upper ones staminate. 
Scales 4-7, membranous, the 2 lower empty, narrow, unequal, the flowering scales similar 
to the second, obtuse or acute at the summit, awnless, sometimes mucronateor short-awned 
at or just below the apex, the upper scales gradually smaller, the upper 1 or 2 often empty ; 
palet hyaline, 2-keeled, 2-toothed. Stamens 3, Styles very short. Stigmas plumose. 

1. Koelerla ctist^ta (L. ) Pers. Stems tufted, erect, rigid, often pubescent just be- 
low the panicle, 3-8 dm. tall : leaf -sheaths smootli or rough, sometimes pubescent ; blades 
2-30 cm. long, 1-3 mm. wide, erect, flat or involute, sometimes hirsute : panicle 2-18 cm. 
long, pale green, shining, usually contracted or spike-like, its branches generally erect: 
spikelets 2-5-flowered, 4-6 mm. long, the scales acute, the flowering scales 3-4 mm. long. 

In dry sandy soil, esrjecially on prairies, Ontario to British Columbia, Penusylvania, Nebraska, 
Texas and Arizona. Also in Europe and Asia. Summer and fall. 

106. MELICA L. 

Perennial grasses, with flat or convolute leaf-blades and contracted or open panicles 
which are sometimes almost racemose. Spikelets few-many, erect or nodding, 1-several- 
flowered, the flowers perfect or the upper ones staminate. Scales 3-several, the 2 lower 
empty, membranous or liyaline, obtuse or acutish, unequal in length, the flowering scales 
larger, membranous, the lateral nerves vanishing at the broad hyaline margin, acute or ob- 
tuse at the apex, the remaining scales empty, gradually smaller, convolute and involving 
each other and forming a clavate to obovoid mass ; palet shorter than the scale, 2-keeled. 
Stamens 3. Styles distinct. Stigmas plumose. Melic Gras?. 

Second scale much shorter than the 3-5-fIowered spikelet. 

Spikelets few : branches of the panicle spreading or ascending. 1. 3/. diffusa, 

Spikelets usually numerous : branches of the panicle erect. 2. M. parviflora. 

Second scale nearly equalling the 2-flowered spikelet. 3. M. mutica, 

1. Melica dlflfusa Pursh. Stems 4-12 dm. tall, erect, tufted : leaf-blades 1-2 dm. 
long, 4-8 mm. wide, rough : panicle 1.5-2 dm. long, open, its branches spreading or as- 
cending : spikelets usually numerous, about 3-flowered, 9-11 mm. long, nodding, on slender 
pubescent pedicels, the flowering scales 7-9 mm. long, acute or obtuse, hispidulous. 

In rich soil, Pennsylvania to Missouri, Virginia, Kentucky and Texas. Spring and summer. 

2. Melica parviflora (Porter) Scribn. Stems 4-8 dm. tall, erect, rough : leaf- 
blades 1-2.5 dm. long, 2-4 mm. wide, rough: panicle 1-2 dm. long, contracted, its 
branches erect : spikelets few^, 4-5-flowered, 10-13 mm. long, nodding, on slender strongly 
pubescent pedicels, the flowering scales 7-8 mm. long, acutish, hispidulous. 

On prairies, Kansas and Colorado to Arizona and Texas. Summer. 

3. Melica mutlca Walt. Stems 3-9 dm. tall, erect, commonly slender : leaf-sheaths 
rough; blades 1-2.5 dm. long, 2-10 mm. wide, rough: panicle 1-2.5 dm. long, narrow, 
its branches spreading or ascending : spikelets 7-9 mm. long, about 2-flowered, nodding, 
on flexuous pubescent pedicels, the flowering scales 6-8 mm. long, usually very obtuse. 

In rich soil, Pennsylvania to Wisconsin, Colorado and Texas. Summer. 

107. KORYCARPUS Zea. 

Perennial grasses, with long flat leaf-blades and elongated narrow panicles. Spikelets 
few, erect, narrow, 3-5-flowered, the rachilla fragile and articulated between the perfect 



POACKAE 



151 



flowers. Scales 5-7, the 2 lower empty, the first narrow, acute, the second longer and 
broader, keeled, acuminate or mucronate, the flowering scales broader, rounded on the 
back, acuminate or mucronate, at lengtli coriaceous and shining, tlie remaining scales 
empty, gradually narrower, involving each other ; palet thin, 2-keeled. Stamens 2, or rarely 
solitary in each flower. Styles short, distinct. Stigmas i)lumose. 

1, Korycarpus diandrus (Michx. ) Kuntze, Stems 4-12 dm. tall, erect, rough be- 
low the panicle : leaf-sheaths overlapping, confined to the lower part of the stem, some- 
times pubescent ; blades 2-6 dm. long, 1-2 cm. wide, commonly rongli : panicle, often 
reduced to a raceme, 5-20 cm. long, its branches erect : spikelets 12-10 mm. long, 3-5- 
flowered, the flowering scales abruptly acuminate. {^Diarrhena Americana Eeaiiv.] 

In rich woods, Ohio to Kansas, Georgia, Tennessee and the Indian Territory. Summer and fall. 

108. UNIOLA L. 

Usually tall perennial grasses, with flat or convolute leaf-blades andc(mtracted or open 



1. t/. Inxa. 



3. U, nitida. 



panicles, the branches sometimes nodding. Spikelets many, erect, or sometimes nodding, 
laterally compressed, 2-edged, 3-many-flowered, the flowers perfect or the upper ones 
staminate. Scales 6-many, compressed-keeled, sometimes winged, the lower 3-G empty, 
gradually enlarging, the flowering scales many-nerved, similar to the upper ones of the 
lower empty scales but larger, the remaining scales, if any, empty ; palet somewhat rigid, 
2-keeled, the keels narrowly winged. Stamens 1-3. Styles distinct. Stigmas plumose. 

Stamen 1 ; not strand grasses. 

Inflorescence long and very slender,'usually nodding at the apex. 
Leaf-sheaths glabrous. 

Leaf-sheaths, at least the lower ones, strongly hirsute. 2. V, longifolia. 

Inflorescence not long and slender. 

Spikelets less than 2 cm. long, the scales less than 10. 

Small empty scales at the base of the spikelet 3 : flowering scales ascend- 
ing, longer than the acute palet: inflorescence usually with long 
spreading branches. 
Small empty scales at the 'base of the spikelet 4 or 5: flowering scales 
widely spreading, equalled or exceeded by the long-acuininate 

palet: inflorescence with short branches. 4. V. ornithoryncha, 

Spikelets 2.5-1 cm. long, oval to ovate, the scales 10-20. 5. {/. Intifolia, 

Stamens 3 : strand grass. 6. U. paniciilata. 

1. Unlola Idxa (L. ) B.S.P. Stems 4-12 dm. tall, erect, slender: leaf-blades 1-4 
dm. long, 2-6 mm. wide, usually erect, each attenuate into a long tip : panicle slender, 
1-3 dm. long, erect, strict, or nodding at the summit, its branches erect : spikelets about 
6 mm, long, 3-6-flowered, the flowering scales 4-5 mm. long, acuminate, spreading in 
fruit. [ Z7. gracilis Michx. ] 

In sandy soil, Long Island to Pennsylvania, Kentucky, Florida and Texas. Summer and fall. 

2. Uniola longifolia Scribn. Stems tufted, 8-12 dm. tall : leaf-sheaths, at least the 
lower ones, densely hirsute; blades flat, 3 dm. long or less, narrowed at both ends, 6-12 
mm. wide: panicle 2-4.5 dm. long, its branches short and appressed, or the lower ones 
sometimes long and ascending : spikelets 3-4-flowered, usually about 6 mm. long, the flow- 
ering scales about 5 mm. long. 

In dry usually sandj" soil, Tennessee to Florida and Louisiana. Summer and fall. 

3. TJniola nitida Baldw. Stems 6-15 dm. tall : leaf -blades 2 dm. long or less, 4-8 
mm. wide: panicle 1-1.5 dm. long, its branches spreading or ascending, the larger ones 
4-6 cm. long, or sometimes reduced to a raceme : spikelets 1 1.5 cm. long. 

In low woods, Georgia and Florida to Louisiana. Spring and summer. 

4. Uniola omithorhyncha Nees. Stems 2.5-6 dm. tally slender: leaf-blades flat, 
6-12 cm. long, 4-7 mm. wide : panicle 4-8 cm. long, its branches short and ascending, 
sometimes bearing but a single spikelet : spikelets crowded, 8-10 mm. long, broader than 
long, the flowering scales long-acuminate. 

In low woods, Mississippi and Louisiana. Summer and fall. 

5. Uniola latifolia Michx. Stems 6-15 dm. tall, erect : leaf-blades 1-2.5 dm. long, 
6-25 mm. wude, flat, the base often ciliate : panicle lax, 1.5-2.5 dm. lonsr, its long branches 
filiform and pendulous : spikelets many-flowered, oval to ovate, much flattened, 2.5-4 cm. 
long, on long capillary pendulous pedicels, the flowering scales 9-12 mm. long, ciliate- 
hispid on the winged keel. 

In moist places, Pennsylvania to Illinois, Kansas, Florida and Texas. Summer and fall. 

6. Uniola panicui^ta L. Stems 1-2.5 m. tall, erect : leaf-blades 3 dm. lon^ or 
more, about 6 mm. wide, involute, at legist when dry, attenuate into long slender tips : 
panicle 2-3 dm. long or more, its branches erect or ascending, strict, rigid : spikelets 



152 



roACEAK 



many-flowered, ovate to oval when mature, 12-25 mm. long, the flowering seales 8-10 mm. 
long and hispidulous on the keel. 

In sands alon^ the seacoast, Virginia to Florida and Texas. Also in the West Indies and South 
America. Fall. Sea Oats. 

109. DISTfcHLIS Eaf. 

Perennial dioecious grasses, with rigid creeping or decumbent stems concealed by the 

overlapping leaf-sheaths, stiff flat or convolute leaf-blades, and contracted panicles. 

Spikelets many-flowered, unisexual, more numerous in the staminate than in the pistillate 

panicles, the rachilla continuous in the staminate, articulated in the pistillate spikelets. 

Scales many, acute, keeled, the 2 lower empty, narrow, the flowering scales longer and 

broader, firm-membranous or nearly coriaceous ; palet compressed, 2-keeled, the keels 

sometimes narrowly winged. Stamens 3. Styles thickened at the contiguous but distinct 

bases, moderately long. Stigmas plumose. 

1. Distichlis spicata (L. ) Greene. Stems 1-6 dm. long, erect, or often decumbent 
at the base, from a long rootstock : leaf-sheaths overlapping and often crowded ; blades 
1-15 cm. long, 2-4 mm. Avide, flat or involute : panicle dense and spike-like, 2-6 cm. long, 
its branches erect : spikelets 8-18 nun. long, 6-16-flowered, pale green, the flowering scales 
3-5 mm. long, acute or acuminate. [/). maritima Eaf.] 

On salt meadows along the Atlantic coast from Maine to Florida and Texas, on the Pacific Coast, 
and in saline soil throughout the interior. Summer. Spike Grass. 

110. DACTYLIS L. 

Perennial usually tall grasses, with flat leaf-blades and open or contracted panicles. 
Spikelets in head-like clusters which are unilaterally azTanged and crowded at the ends of 
the branches, 3-5-flowered, the flowers perfect or the upper ones staminate. Scales 5-7, 
keeled, the 2 lower empty, unequal, mucronate, the second the larger, the flowering scales 
larger, more rigid, the keel ciliate and excurrent as a mucro or short awn ; palet nearly 
as long as the scale, 2-keeled. Stamens 3. Styles distinct. Stigmas plumose. 



1. Dactylis glomerata L. Stems 6-12 dm. tall, tufted, erect; leaf-sheaths smooth 
or rough ; blades 7-23 cm. long, 2-6 mm. wide, flat, rough : panicle 7-20 cm. long, its 
branches spreading or ascending in flower, erect in fruit : spikelets in dense capitate clusters, 
3-o-flowered, the flowering scales 4-6 mm. long, rough, pointed or short -awned, ciliate on 
the keel. 

In fields, meadows and waste places, N'ew Brunswick to Manitoba, Georgia and Colorado. Natu" 
ralized from Europe. Summer. Okchakd Gkass. 

111. POA L. 

r 

Annual or perennial grasses, rarely dioecious, with flat leaf-blades and open sometimes 
contracted panicles, the branches often drooping. Spikelets 2-6-flowered, the flowers per- 
fect, or rarely unisexual, the glabrous or rarely somewhat pilose rachilla articulated between 
the flowers. Scales 4-8, membranous, keeled, acute or obtuse, awnless, the 2 lower empty, 
persistent, the flowering scales usually longer, frequently pubescent on the callus and the 
midnerve and marginal nerves, the hairs often long and curled ; palet shorter than the 
scale, 2-nerved or 2-keeled. Stamens 3. Styles short, distinct. Stigmas plumose. Meadow 

Gkass. Spear Grass. Blue Grass. 

Annuals or biennials : stems densely tufted, low, usually less than 3 dm. long. 

^lowering scales distinctly 5-nerved, not webby at the base. 1. P. annua. 

Flowering scales 3-nerved or sometimes with a pair of obscure additional 
nerves, webby at the base. 
Perennials: stems usually exceeding 3 dm. in height. 
A. Plants green, with no long rootstocks. 

a. Flowering scales with long crimped hairs at the base. 
Flowering scales with only the midnerve pubescent. 

Flowering scales 2.5 mm. long, the midnerve sparsely pubescent : plant 

yellowish green. 
Flowering scales 3.5 mm. long, the midnerve densely pubescent : plant 
green . 
Flowering scales with the midnerve and lateral nerves pnbescent. 
* Panicle open, its branches spreading : spikelets not crowded. 

Midnerve of the flowering scale pubescent only below the middle. 
Flowering scales about 3 mm. long : basal leaves usually rela- 
tively short. 
Flow^ering scales 4-5 mm. long: basal leaves very long, often 

equalling the stem in length or nearly as long. 6. P. hrevifolia. 



2. P. Chapmaniana, 



3. P, tiinalis. 

m 

4. P. alsodes. 



3 

1 



5, P. prataisis. 



rOACEAK 



153 



Midnerve of the flowering scale pubescent the whole length, or 

nearly so. 

Flowering scales about 2.5 ram. long, obtuse. 7. 1\ Bylveatrif. 

Flowering scales alx)ut 4 mm. long, acute. 8. P. M'olfiL 

** ranicle contracted, its branches erect or nearly so : spikelets crowded. 
Flowering scales stnmgly pubescent at the base with very long 

crimped hairs, the m'idnerve and lateral nerves pubescent. 9. P, arachiufera. 

Flowering scales with fewer crimped hairs at the base, the nerves 

all glabrous. 10. P. glahrcBceM, 

b. Flowering scales with no crimped hairs at the base. 

Panicle loose and open, its In-anches long and widely spreading and spike- 
let-bearing only above the middle. 11. P. cmttimnalis. 
Panicle contracted, its branches short and erect or nearly so, spikelet- 

bearing to the base or nearly so. 12. P. pratericola. 

B. Plants dull bluish green, with long stout often branching rootstocks : stems 

much compressed. 13. P. comprcssa. 

1. Poa annua L, Stems 5-30 cm. tall, erect, or decumbent at tl)e base : leaf-sbeaths 
loose, usually overlapping* ; blades 1-10 cm. long, 1.5-3 mm. wide : |)anicle 1-10 cm. long, 
its l)ranches spreading: spikelets 3-5-flowcred, 3-5 mm. long, the flowering scales 2.5-3 
mm. lonij. 

In wiiste and cultivated places nearly throughout Xorth America. Naturalized from Europe. 
Native also of Asia. Spring to fall. 

2. Poa Chapmaniana Scribn. Stems 7-15 cm. tall, erect, rigid : leaf-sheaths tight, 

mostly at the base of the stem ; blades 1-2.5 cm. long, 2 mm. wide or less : panicle 2.5-6 

cm. long : spikelets 3-7-flowered, 2.5-3 mm. long, the flowering scales obtuse, webbed at the 

base and sometimes with hairs on the more prominent nerves. [P. cristata Chapm., not 
AV'alt.] 

In dry soil, Kentucky and Tennessee to Georgia, Florida and Alabama. Spring. 

3. Poa trivialis L. Stems 3-9 dm. tall, usually decumbent at the base : leaf-sheaths 
very rough ; blades 5-18 cm. long, 2-4 mm. wide, rough : panicle 1-1.5 dm. long : spike- 
lets 2-3-iiowered, 3 mm. long, the scales acute, the flowering scales 2-3 iuni. long, 5-nerved, 
the intermediate nerves prominent. 



In meadows and Avaste places, New Brunswick to Michigan and Georgia. Naturalized from 
Europe. Summer. 

4. Poa alsodea A. Gray. Stems 2-8 dm. tall: leaf-blades usually rough, 2-4 mm. 
wide, those on the stem 5-20 cm. long, the basal ones longer : panicle 8-20 cm. long, its 
branches spikelet-bearing at the ends : spikelets 2-3-flowered, about 5 mm. long, the flow- 
ering scales acute, about 4 mm. long, the intermediate nerves very faint. 

In woods and thickets, Nova Scotia to Ontario, Minnesota, North Carolina and Tennessee. Spring 
and summer. 

5. Poa prat^nsis L. Stems 3-12 dm. tall : leaf-blades smooth or rough, 1-6 mm. 
Avide, those on the stem 5-15 cm. long, the basiil much longer : panicle 6-20 cm. long, us- 
ually pyramidal : spikelets 3-5-flowered, 4-5 mm. long, the scales acute, the flowering 
scales 3 mm. long, 5-nerved. 

In meadows, fields and woods, almost throughout North America. Widely cultivated for hay. 
Also in Europe and Asia. Summer. Kentucky Blue Guass. Jv^e Grass. 

6. Poa brevifolla Muhl. Stems 3-9 dm. tall, erect : leaf-blades smooth beneath, 
rough above, 2-4 mm. wide, abruptly acute, those on the stem 1-10 cm. long, the upj^er- 
most sometimes almost wanting : panicle 6-13 cm. long, its branches widely spreading or 
often reflexedj spikelet-bearing at the ends : spikelets 3-6-flowered, 5-7 mm. long, the 
flowering scales 4-5 mm. long, obtuse, the intermediate nerves prominent. 

In rocky woods, southeastern New York to Illinois, North Carolina and Tennessee. Spring and 
summer. 

7. Poasylv^stris A. Grav. Stems 3-9 dm. tall, slender : leaf-blades smooth beneath, 
rou^h above, 2-6 mm. wide, tlaose on the stem 4-15 cm. long, the basal much longer : 
panicle 7-18 cm. long, the branches spreading or ascending, sometimes reflexed when old, 
SDikelet-beuring at the ends : spikelets 2-4-flowered, 2-4 mm. long, the flowering scales 
about 2.5 mm, long, obtuse. 

In thickets and meadows, New York to Wisconsin, Nebraska, Georgia and Louisiana. Summer. 




ered, 5-6 mm. long, the acute flowering scales about 4 mm. long, strongly pubescent on the 
midnerve and the lateral nerves, the intermediate nerves very prominent. 

In moist soil, Illinois, Tennessee and Kansas. Summer. 

9. Poa arachnlfera Torr. Stems tufted, 3-9 dm. tall : leaf-blades erect, usually 
folded when dry, smooth beneath, rough above, 4-23 cm. long, 3-6 mm. wide, abruptly 
acute : panicle dense and contracted, sometimee interrupted below, 7-16 cm. long, its 



154 



POACEAE 



branches erect or nearly so : spikelets numeroiiSj 4-7-tlowered, the scales acuminate, the 
flowering scales 4-5 mm. long. 

On prairies, Kansas to New Mexico, Louisiana and Texas. Also introduced into Florida. Spring. 

10. Poa glabr^scens Nash. Stems tufted, 2-5 dm. tall : leaf-blades erect, 1.5 dm. 
long or less, 2-5 mm. Avide, rough above: panicle 4-15 cm. long, 1-3 cm. wide : spikelets 
5-9-flowered, the flowering scales 4-5 mm. long. 

On prairies, Indian Territory and Texas. Spring. 

/ 11. Poa autumnklis Muhl. Stems 3-9 dm. tall : leaf-blades 2 mm. wide or less, 
smooth beneath, rough above, those on the stem 4-15 cm. long, the basal much longer : 
panicle 7-22 cm. long, the brandies long and slender and spikelet -bearing at the ends : 
spikelets 3-5-flowered, 5-6 mm. long, the flowering scales rounded or retuse at the apex, 
3-4 mm. long, pubescent on the lower part of the internerves. [P. flexuosa Muhl.] 

In woods. New Jersey and Pennsylvania to Kentucky, Florida and Texas. Spring and summer. 

12. Poa pratericola Rydb. & Nash. Stems 3-6 dm. tall, erect, rigid : leaf-sheaths 
usually overlapping ; ligule 2-4 mm. long, acute ; blades smooth beneath, x'ough above, 
1-2 mm. wide, flat or folded, pungently pointed, those on the stem 1-2.5 cm. long, erect, 
the basal ones 7-15 cm. long : panicle contracted, 5-13 cm. long, the branches erect : spike- 
lets 4-7-flowered, 5-7 ram. long, the flowering scales 3-4 mm. long, erose-truncate at the 
apex, strongly silky-pubescent qn the nerves for i their length, the internerves pubescent 
below, the intermediate nerves very obscure. 

In meadows and low pounds, Northwest Territory to Kansas, the Indian Territory and Arizona. 
Spring and summer. 

13. Poa compr^ssa L. Stems 1.5-6 dm. tall, decumbent at the base, from long 
branching rootstocks, much flattened : leaf-sheaths loose, flattened ; blades 2-10 cm. long, 
about 2 mm. wide : panicle usually contracted, the branches erect or ascending : spikelets 
3-9-flowered, 3-6 mm. long, the flowering scales 2-2.5 mm. long, obscurely 3-nerved. 

In cultivated grounds, waste places and woods, almost throughout North America. Natviralized 
from Europe, at least in some places. Also a native of Asia. Summer. Caxadian Blue Guass. 

112. PANICULARIA Fabr. 

Usually perennial, rarely annual, sometimes aquatic grasses, witli commonly flat leaf- 
blades and open or contracted panicles, the branches sometimes drooping. Spikelets usually 
numerous, ovate to linear, few-many-flowered, tlie glabrous rachilla articulated between 
the perfect flowers, the upper flowers sometimes imperfect. Scales few-many, awnless, the 
2 lower empty, obtuse or acute, unequal, the flowering scales longer, obtuse to truncate and 
denticulate, rarely acute or acuminate at the more or less hyaline apex, convex on the back 
but not keeled, usually prominently nerved, the nerves vanishing at the hyaline margin ; 
palet 2-keeled, equalling or shorter than, rarely exceeding, the scale. Stamens 3. Style 
short, distinct. Stigmas plumose. IGlyceria R. Br.] Manna Grass. 

Spikelets ovate or oblong, 8 mm. lonff or less. 

Flowering scales very broad, obscurely or at least not sharply nerved. 1. P. ohtusa. 

Flowering scales narrow, sharply and distinctly 7-nerved. 

Panicle elongated, its branches erect or appressed. 2. P. dongata. 

Panicle not elongated, its branches usually spreading or ascending, sometimes 
drooi)ing. 
Flowering scales about 1.5-2 mm. long, obtuse or rounded at the apex. 

Spikelets 2-3 mm. long or less : branches of the panicle often drooping. S. P. nervaia. 
Spikelets 4-6 mm. long : branches of the panicle ascending or spreading. 4. P. Americana. 
Flowering scales 2.5-3 mm. long, truncate and denticulate at the apex. 5. P. pallida, 

Spikelets linear, 12 mm. long or more. 

Flowering scales 4-5 mm. long, obtuse, equalling or exceeding the obtuse palet. 6. P. fluitans. 
Flowering scales 6-8 mm. long, acute, much shorter than the acuminate palet. 7. P. acutiflora. 

1. Panlcularia obtusa (Muhl.) Kuntze, Stems 3-9 dm. tall, erect, stout, ri^id : 
leaf -sheaths strongly striate, the lower overlapping ; blades 1.5-4 dm. long, 4-8 mm. wide, 
usually stiff, erect or ascending, rough above : panicle 7-20 cm. long, contracted, dense, 
the branches erect : spikelets 3-7 -flowered, 4-6 mm. long, the flowering scales 3 mm. long. 

In swamps, New Brunswick to New York, Delaware, Maryland and North Carolina. Summer. 

2. Panicularia elong^ta (Torr. ) Kuntze. Stems 6-9 dm. tall : leaf-blades lax, 1.5-3 
dm. long, 3-6 mm, wide, long-acuminate, rongh above : panicle elongated, contracted, 

ally nodding at the summit, 1.5-3 dm. long, the branches erect or appressed : spikelets 

3-4-flowered, 3-4 mm. long, the flowering scales about 2 mm. long, obtuse or acutish. 

In wet woods and swami)s, Newfoundland to Quebec, Minnesota, Kentucky and North Carolina. 
Summer and fall. 

3. Panlcularia nerv^ta ( Willd. ) Kuntze. Stems 3-9 dm. tall : leaf-sheaths usually 
rough ; blades 1.5-3 dm. long, 4-10 mm. wide, rough above: panicle 7-20 cm. long, often 



POACEAE 



155 



purple, the branches spreading, ascending, or often drooping: spikelets 3-7-Howcred, 2-:> 
mm. long, the flowering scales about 1.5 mm. long, obtuse or rounded. 

In -vvet places, Newfoundland to British Columbia, Florida, Texas and Mexico. Summer and fall. 

4. Panicularia Americana (Torr. ) MacM. Stems 9-15 dm. tall : leaf-sheaths loose, 
sometimes rough ; blades 2-3 dm. long or more, 6-16 mm. wide, rough above : panicle 2-4 
dm. long, the lower branches 1-2 dm. long ; spikelets 4-7-fl()\vered, 4-6 mm. long, the 
flowering scales about 2 mm. long. 

In wet soil, New Brunswick to Alaska, Tennessee, Colorado and Nevada. Summer. 

5. Panicularia pdllida (Torr.) Kuntze. Pale green. Stems 3-9 dm. long, assur- 
gent : leaf-bhides 5-15 cm. long, 2-4 ram. wide, rongh above: panicle 4-lS cm. long, its 
branches spreading or ascending : spikelets 4-8-flowered, 5-7 mm. long, the flowering scales 
2.5-3 mm. long, truncate and denticulate at the apex. 

In shallow water, New l^runswick to Ontario, Virginia, Tennci^see and Indiana. Summer. 

6. Panicularia fluitans (L. ) Kuntze. Stems 1-1.5 m. long, flattened, usually stout, 
often rooting from the lower nodes : leaf-sheaths loose, usually overlapping ; blades 1-3 
dm. long or more, 4-12 mm. wide, rougli, often floating : panicle 2-4.5 dm. long, its 
branches finally ascending : spikelets 7-13-flowered, 2-2.5 cm. long, the flowering scides 
4-5 mm. long, thick, oblong, rounded or truncate at the erose apex, hispidulous. 

In wet places or in water, Newfoundland to British Columbia, North Carolina, Kentucky, Iowa 
and California. Summer and fall. 

7. Panicularia acutiflora (Torr.) Kuntze. Stems 3-6 dnj. tall, flattened, erect from 
a decumbent base : leaf-sheaths loose, smooth ; blades 7-15 cm- long, 4-0 mm. wide, 
rough above: panicle 1.5-3 dm. long, its branches erect or appressed : spikelets 5-12- 
flowered, 2.5-4.5 cm. long, the flowering scales 6-8 mm. long, lanceolate, acute, smooth. 

In wet places, Maine to southern New York, Ohio and Tennessee. Summer. 



113, FESTUCA L. 

Usually perennial, rarely annual, tufted grasses, with flat or convolute sometimes seta- 
ceous leaf-blades and contracted often spike-like or open panicles which are sometimes 
nearly racemose. Spikelets 2 -several-flowered, the flowers perfect or the upper onesstami* 
nate, the rachilla articulated between the flowers. Scales 4-several, membranous, the 2 
lower empty, unequal, acute, keeled, the flowering scales rounded on the back, at least 
below, acute or rarely obtuse, usually more or less awned, occasionally awnless, the remain- 
ing scales if any, empty ; palet a little shorter than the scale, 2-keeled. Stamens 1-3- 
Styles very short, distinct, terminal or nearly so. Stigmas plumose. Fkscue Grass. 

Annuals : stamens 1 or 2. 

First empty scale less than % as long as the second, usually very small, 1. F. Myuros. 

First empty scale more than % as long as the second. 
Flowering scales not hirsute. 

Spikelets 3-1-flo wered ; flowering scales glabrous or nearly so, appressed to the 

rachilla. . 2. F. parviJUrra, 

Spikelets 6-13-flowered ; flowering scales usually strongly hispidulous, decid- 
edly diverging from the rachilla. ' 3, F, octoflora. 
Flowering scales appressed-hirsute. 4. F. sciurea. 
Perennials : stamens 3. 

Leaf-blades very narrow, 2 mm. wide or less, involute or folded. 

Plants without rootstocks : flowering scales awnless. 5. F. capiUata, 

Plants with long rootstocks : flowering scales short-awned. 6. F, rubra. 

Leaf-blades 3 mm. wide or more, flat. 

Panicle open, its branches at maturity ascending or spreading : spikelets usually 

less tnan 6-flowered. 

Panicle-branches elongated, spikelet-bearing toward the end. 7. F. nutans. 
Panicle-branches not elongated, spikelet-bearing from the middle or below it. 

Flowering scales obtuse, 4-5 ram. long. 8. F. obtusa. 

Flowering scales acute* 6-7 mm. long. 9. F Texana. 

Panicle contracted, its branches erect or appressed : spikelets often lO-flowcrcd. 10. F, daUor. 

1. Festuca Myuros L. Stems 3-6 dm. tall, erect: leaf-blades 5-13 cm. long, sub- 
ulate, involute, erect : panicle usually one-sided, 1-3 dm. long, spike-like, its branches ap- 
pressed : spikelets 3-G-flovvered, tlie flowering scales, exclusive of the awn, 4-6 mm. long, 
narrow, acuminate into an aAvn much longer than itself. 

In waste places and fields, Xew Hampshire to New Jereey and Florida. Naturalized from Europe- 
Summer. 

2. Festuca parviflora Ell. Stems 3-5 dm. tall, slender : leaf-blades 5-10 cm. long, 
about 1 mm. wide : panicle very slender, 1-2 dm. long,^ its branches appressed : spikelets 
3-4-flowered, the flowering scales 4-5 mm. long, exclusive of the awn which is of equal 
length or somewhat longer. 

In dry soil, South Carolina to Florida and Texas. Spring and summer. 



156 



POACEAE 



3. Pestuca octoflora Walt. Stems 1-5 dm. tall, erect, slender, rigid : leaf-blades 
4-8 cm. long, involute, bristle-form : panicle or raceme often one-sided, 2.5-15 cm. long, con- 
tracted, its branches erect, ornearlyso: spikelets 6-13-flowered, 6-10 mm. long, the flower- 
ing scales, exclusive of the awn, 3-5 mm. long, usually very rough, acuminate into an awn 
nearly as long as itself or shorter, or sometimes awnless. [F\ tenella Willd.] 

In dry sandy usually sterile soil, Quebec to British Columbia, Florida, Texas and California. 

Summer, 

4. Festuca sciurea Xutt Stems 1-5 dm, tall, slender : leaf-blades 5 cm. long or 
less, less than 1 mm. wide : panicle slender, 4-15 cm. long, its branches erect or appressed : 
spikelets 3-5-flowered, the flowering scales about 3 mm. long, exclusive of the awn which 
is 2-3 times as long as the scale. 

In dry soil, Florida to the Indian Territory and Texas. Spring and summer. 

5. Festuca capiUkta Lam. Stems densely tufted, erect, 1.5-4 dm. tall, slender, 

glaucous : leaf-sheaths confined to the base of the stem ; blades filiform, the basal ones from 

j-^ as long as the stems, the stem-blades 2.5-4 cm. long : panicle contracted, 1-5 cm. long, 

its branches erect ; spikelets 4-5-fiowered, 4-5 mm. long^ the flowering scales about 2.5 
nmi. long, acute. 

In fields and along roadsides, Mahie, New York and Mississippi. Introduced from Europe. Summer. 

6. Festuca rubra L. Stems 4-8 dm. tall, erect : basal leaf-blades involute-filiform, 
7-15 cm. long, those on the stem shorter, erect, flat, or involute in drying, minutely 
pubescent above : panicle 5-13 cm. long, sometimes reddish : spikelets 3-10-flowered, 8-12 
mm. long, the flowering scales about 6 mm. long, bearing an awn less than its own length. 

In meadows and fields, Labrador to Alaska, and in the mountains to Virginia, Tennessee and 
Colorado. Also in Europe and Asia. Summer. 

7. Festuca nutans Willd. Stems 6-9 dm. tall, slender : leaf-blades 1-3 dm. long, 
4-6 mm. wide, flat, rough above : panicle 1-2.5 dm. long, the lower branches 6-13 cm. 
long : spikelets lanceolate, 3-5-fiowered, 5-6 mm. long, the flowering scales 3-4 mm. long. 

In rocky woods, Nova Scotia to Ontario, Nebraska, Florida and Texas. Summer. 

8. Festuca obtusa Spreng. Stems 6-12 dm. tall : leaf-blades 1-2.5 dm. long, 2-6 
mm. wide, rough above : panicle 7-18 cm. long, the lower branches 4-9 cm. long : spike- 
lets broadly obovate when mature, 3-6-flowered, 5-6 mm. long, the flowering scales 4-5 
mm. long. 

In Avoods and thickets, Pennsylvania and Illinois to Kansas, Georgia, Mississippi and Texas. 
Summer. 

9. Festuca Texkna Ya.sey. Stems 4-8 dm. tall ; leaf-blades 5-15 cm. long, 3-5 mm. 
wide : panicle 1-2 dm. long, its branches stiff" and widely spreading, the lower ones usually 
in pairs : spikelets 2-4-flowered, the flowering scales glabrous, acute, sometimes short-awned. 

In shady places, Oklahoma and Texas. Spring, 

10. Festuca el^tior L. Stems 6-15 dm. tall ; leaf-blades 1-4 dm. long, 4-8 mm. 
wide, rough above : panicle 1-4 dm. long, often nodding at the top, simple to very com- 
pound : spikelets 5-10-flowered, 9-12 mm. long, the flowering scales acute or short-pointed, 
5-6 mm. long, indistinctly 5-nerved. 

In waste places and fields, Nova Scotia to Ontario, North Carolina, Tennessee and Kansas. Natural- 
ized from Europe. Summer. 

114. BROMUS L. 

Annual or perennial grasses, with usually closed leaf-sheaths, flat blades and contracted 
or open sometimes almost racemose panicles, the branches often nodding, Spikelets usually 
large, often drooping, few-many-flowered, the flowers perfect or the upper ones imperfect. 
Scales few-many, membranous, the 2 lower empty, persistent, narrow, unequal, acute or 
the second sometimes short-awned ; flowering scales longer and often broader, rounded 
on the back, at least beloAV, usually awned, rarely awnless, the straight or rarely recurved 
awn dorsal and inserted just below the 2-toothed or shortly 2-cleft apex ; palet shorter than 
the scale, 2-keeled. Stamens 3, rarely fewer. Ovary croA\Tied by a villous appendage, at 
the base of which arise the very short but distinct styles. Stigmas plumose. Brome Grass. 

Chess. Cheat. 

A. Lower empty scale l-ner\'ed, the upper 3-nerved. 

Annuals : stems usually less than 6 dm. tall : awn longer than the flowering scale. 
Spikelets numerous, several on each panicle-branch : flowering scales 8-12 mm. 

long, appressed-hirsute. 1, B, tectorum, 

Spikelets few, 1 or sometimes 2 on each panicle-branch : flowering scales 12-16 

mm. lon^, sparingly hispidulous. 2. B. sterUis. 

Perennials : stems usually exceeding 6 dm. in height : awn shorter than the flower- 
ing scale or wanting. 



rOACEAE 



157 



Flowering scales awnless, or merely awn-pointed. 3. Ji. intrmis. 

Flowering scales with distinct awns. 

Flowering scales glabrous, or pubescent on the margins. 4. B. eiliatus. 

Flowering scales densely pubescent all over the back. 5. Ji. purgans. 

B. Lower empty scale 3-ner\*ed, the upper 5-9-nerved. 
Flowering scales rounded on the back, at least below. 

Leaf-sheaths glabrous: nerves of the turgid fruiting scales obscure. 6. B. secaliaus. 

Leaf-sheaths softly and densely pubescent with reflexed hairs ; nerves of the 
flowering scales prominent. 

Flowering scales compressed, keeled. 



7. 1i. raccmoHUs, 

8. B. unioloidf i? , 



1. Bromus tectorum L. Stems 1.5-6 dm. tall, erect : leaf-slieaths, at least tlie lower 
ones, softly pubescent; blades 2.5-10 cm. long, 2-4 mm, wide, softly pubescent : panicle 
5-15 cm. long, the branches slender and drooping : spikelets numerous, 5-8-flowered, on 
capillary recurved pedicels, the flowering scales 8-12 mm. long, acuminate, usually rough 
or hirsute, the awn 1-1.5 mm. long. 



In fields and waste places, Massachusetts to Indiana, Colorado, AVashington, Virginia and Missis- 
sippi. Naturalized from Europe. Spring and summer. 

2. Bromus st6rill3 L. Stems 3-6 dm. tall: leaf-sheaths sometimes pubescent ; blades 
7-23 era. long, 2-6 mm. Avide, commonly pubescent : panicle 1-2.5 dm. long, its branches 
usually widely spreading, stiff*: spikelets few, 5-10-flowered, spreading or pendulous, the 
flowering scales 7-nerved, hispidulous on the nerves, the awn 1.5-2.5 cm. long. 

In waste places and on ballast. Locally naturalized from Europe. Summer. 

3. Bromus in6rmi3 Leyss. Stems tufted, 8-12 dm. tall : leaf-sheaths glabrous ; 
blades 1.5-2.5 dm. long, 4-6 mm. wide, glabrous: panicle 1.5-2.5 dm. long, oblong, its 
branches ascending : spikelets 2-2.5 cm. long, about 5 mm. wide, oblong, erect, the flower- 
ing scales 10-12 mm. long. 

In fields and waste places, escaping from cultivation, especially in the West. Summer. 

4. Bromus eiliatus L. Stems 7-12 dm. tall : leaf-sheaths retrorsely short-pilose or 
almost glabrous ; blades lax, 2.5-4 dj)i. long and about 1 cm. wide, sparsely pubescent, or 
sometimes nearly glabrous : panicle 1.5-3 dm. long, the lower branches drooping : spikelets 
5-9-flowered, 15-22 mm. long, the flowering scales 10-12 mm. long, pubescent on each 
side for about f the length, the awn straight, slender, 3-5 mm. long. 

In woods, Newfoundland to New York, Minnesota and Manitoba.— The variety B, ciliatxu laevl- 
(flUmu Scribn. differs mainly in having the flowering scales glabrous, or with a few hairs at the base. 
Ontario, Maine and North Carolina. Summer. 

5. Bromus ptlrgans L. Stems 7-15 dm. tall : leaf -sheaths usually coarsely retrorsely 
pubescent; blades 1.5-3 dm. long, 5-15 mm. wide, glabrous, or pubescent on the nerves 
above: panicle lax, nodding, 1.5-3 dm. long : spikelets 7-11 -flowered, 2-2.5 cm. long, the 
flowering scales 10-12 mm. long, pubescent all over the back, the awn straight, 4-6 mm. 
long. 

In woods, Canada and New England to Wyoming, Florida and Texas. Summer. 

6. Bromus secdiinus L. Stems 3-9 dm. tall : leaf-sheaths commonly glabrous; blades 
5-23 cm. long, 2-6 mm. wide, sometimes hairy : panicle 5-10 cm. long, its branches as- 
cending or drooping : spikelets turgid when in fruit, 6-10-flowered, the flowering scales 
6-8 mm. long, rough toward the apex, awnless, or bearing a straight awn 8 mm. long or 
less between the obtuse short teeth. 

Tn fields and waste places almost throughout temperate North America. Naturalized from Europe 
Summer. 

7. Bromus racemosus L. Stems 3-7 dm. tall, commonly puberulent just below the 

f)anicle: leaf-sheaths, at least the lower ones, rather densely pubescent ; blades 7-14 cm. 
ong, pubescent, or sometimes glabrous above : panicle usually simple, sometimes com- 
pound : spikelets 1.5-2 cm. long, generally nodding in fruit, acute, 5-9-flowered, the 
flowering scales elliptic, 6-8 mm. long, fmiooth or rough, the awn 5-8 mm. long, arising 
just below the apex. 

In waste places, Cape Breton Island and Maine to Pennsylvania and Delaware.— The variety B. 
racemosus commtUAtus (Scnrad.) Hook, has the spikelets 2-2.5 cm. lonjf, and somewhat broader flowering 
scales and the panicle larger. In similar situations and generally distributed throughout the East a« 
far south as Tennessee. Summer, 

8. Bromus uuioloides fWilld.^ H.B.K. Annual. Stems 5-10 dm. tall: leaf- 



sheaths commonly pubescent, or sometimes glabrous ; blades rough, sometimes sparingly 
pubescent: panicle usually long and narrow, 1.5-5 dm, long: spikelets 2-3.5 cm. long, 
7-11-flowered, the flowering scales thick, firm, 12-16 mm. long, each commonly with a 
short stout awn. 

In waste places, Alabama to Texas and California. Also in Mexico.— The variety B. uuioloides 
RaenkeAnus (Presl.) Shear, differs in its smaller size, and almost simple panicle with smaller gpikeletg. 
In similar situations, Florida to Texas and California. Spring and summer. 



158 



POACEAE 



115. LOLIUM L. 

Annual or perennial grasses, with flat leaf-blades and terminal simple usually elongated 
spikes. Spikelets with the edge (backs of the scales) to the rachis, scattered, erect, alter- 
nate, sessile and solitary in the rachis excavations, compressed, several-many-flowered, the 
flowers perfect or the upper ones imperfect, the rachilla articulated between the flowers. 
Scales rigid, rounded on the back, obtuse to acuminate, awned or awnless, the nerves con- 
nivent above or confluent into the awm, the lower scale of the lateral spikelets and the 2 
lower scales of the terminal spikelet empty, narrow, longer than the remaining scales, thin 
flowering scales short, imbricated ; palet shorter than the scale, 2-keeled- Stamens 3. 
Styles distinct, very short. Stigmas plumose. Darxkl. Rye Grass. 

Empty scale shorter than the spikelet. 

Flowering scales awnless. 

Flowering scales awned. 
Empty scale equalling or extending beyond the flowering scales. 3. X. temulentam. 

m 

1. Loliuxn per6ane L. Stems 1.5-8 dm. tall : leaf-blades 5-13 cm. long, 2-4 mm. 
wide: spike 7-20 cm. long: spikelets 5-10-flowered, 8-12 mm. long, the empty scale 
strongly nerved, the flowering scales 4-6 mm. long, acuminate, awnless. 

In waste places and cultivated ground, almost throughout the northern United States. Natural- 
ized from Europe. Summer, 



1. X. pcrenne, 

2. X. Italicum, 



2. Iiolium ItAlicum A. Br. Stems 6-10 dm. tall : leaf-sheaths glabrous ; blades 
1-2 dm. long, 3-7 mm. wide : spikes 2-3 dm. long: spikelets 20-30, 1.5-2 cm. long, the 
flowering scales bearing an awn equalling or a little shorter than the body. 

In fields and waste places, sparingly introduced. Naturalized from Europe. Summer. 

3. liOlium temul6ntiim L. Stems 6-12 dm. tall : leaf -blades 1-2.5 dm. long, 2-6 
mm. wide, rough above : spike 1-3 dm. long : spikelets 4-8-flowered, 1-2 cm. long, the 
empty scale strongly nerved, the flowering scales awned or awnless. 

In waste places and c-ultivated ground, Xcw Brunswick to Michigan, Georgia and Kansas. Summer 



116. AGROPYRON J. Gaertn. 

Annual or perennial grasses, with flat or convolute leaf-blades and terminal usually 
rigid 2-4-sided spikes. Spikelets compressed, with the side (edge of the scales) toward 
tlie continuous or rarely articulated, rachis, sessile, alternate, single in the rachis excava- 
tions, appressed or oblique to the rachis, several-many-flowered, the flowers perfect or the 
upper ones imperfect, the rachilla articulated between the flowers. Scales several-many, 
the 2 lower empty, the flowering ones broader, rigid, rounded on the back, obtuse to 
acuminate, awned or awnless, the nerves connivent at the apex or confluent into the awn, 
the remaining scales if any empty ; palet shorter than the scale, 2-keeled, the keels usually 
ciliate. Stamens 3. Styles very short, distinct. Stigmas plumose. AVheat Grass. 

Spikelets much compressed, lanceolate to ovate, ascending. 1. A. oecidentale, 

Spikelets nearly terete, linear, erect. 2. A. repens. 

1. A gropyxon oecidentale Scribn. Pale green, glaucous. Stems 4-12 dm. tall, 
from a slender creeping rootstock : leaf-blades erect, 5-20 cm. long, 4-8 mm. wide, rough 
above» smooth beneath, becoming involute Avhen dry : spike strict, 1-2 dm. long :spikelets 
crowded, diverging from the rachis, 1.25-2.5 cm. long, 6-12-flowered, the empty scales 



acuminate, awn-pointed, hispidulous on the keel, the flowering scales 10-12 mm. long, 
acute, sometimes awn-pointed, glabrous or sparingly pubescent. 

On prairies and high plains, Manitoba and Minnesota to Oregon, Missouri and Texas. Summer. 

2. Agropyron rilpens (L.) Beauv. Stems 3-12 dm. tall, from a long rootstock: 
leaf-blades 7-30 cm. long, 2-10 mm. wide, smooth beneath, hirsute above': spike 5-20 cm. 
long, strict: spikelets 3-7 -flowered, the empty scales strongly 5-7 -nerved, usually acute or 
awn-pointed, sometimes obtuse, the flowering scales glabrous, acute or short -awned. 

Tn fields and waste places, almost throughout North America. Naturalized from Europe. Summer 
and fall. Couch Grass. Quitch Grass. 

117, HORDEUM L. 

Annual, rarely perennial, grasses, with flat leaf-blades and terminal cylindric usually 
dense spikes which are often concealed by the long awns. Spikelets in alternate 3's 
(rarely in 2's) at each node of the articulated rachis, sessile or short-pedicelled, the lateral 
often much reduced, 1 -flowered, the flower perfect, or in the lateral spikelets often imper- 



^\ 



:j 



rOACEAE 



159 



feet or wanting, the racliilla extending beyond the flowers as a long slender bristle or 
sometimes bearing a narrow terminal scale. Scales 3 or 4, tlie 2 lower empty, awn-like, 
sul)ulate, lanceolate, or narrowly linear, rigid, persistent, the empty scales at each rachis- 
node forming an apparent involucre and falling with the readily deciduous rachis joints, 
the flowering scales lanceolate, rounded on the back, the nerves confluent into astraiglit or 
divergent awn, or in the lateral spikelets awnless and sometimes much reduced ; palet 
shorter than the scale, 2-keeled, Stamens 3. Styles very short, distinct. Bahlfa". 

Each cluster of spikelets with all the empty scales bristle-like. 1. //. nodosum. 

Each cluster with four of the empty scales dilated above the base. 2. IL pusiUum, 

1. Hordeum nodosum L. Stems 1.5-6 dm. tall, erect, or sometimes decumbent : 
leaf-blades 4-13 cm. long, 2-6 mm. wide, flat, rough ; spike 2.6-9 cm. long : spikelets us- 
ually in 3's, the flowering scale of the central spikelet 6-8 mm. long, exclusive of tlie awn 
which is 6-12 mm. long, the corresponding scale in the lateral spikelets much smaller and 
short-stalked. [//. pratense Iluds.] 

In meadows and waste places, Indiana to Minnesota, British Columbia, Alaska, Georgia, Texas 
and California. Also in Europe and Asia. Summer. 

2. Hordeum puslllum Nutt. Stems 1-4 dm. tall, erect, or decumbent at the base : 
leaf-blades 1-8 cm. long, 1-4 mm. Avide, erect, rough above : spike 2.5-8 cm. long : spike- 
lets usually in 3's, the scales awned, the empty ones rough, the flowering ones sJiiooth, 
that of the central spikelet 6-8 mm. long, short-awned, tlie corresponding scale in the 
lateral spikelets smaller and very short-stalked. 

In dry soil, Ontario to British Columbia, Nebraska, Arkansas, Texas and California ; also sparingly 
introduced into the southeastern United States. Summer. 

118. SITANION Raf. 

Erect perennial grasses, with flat or involute leaf-blades and a terminal dense cylin- 
dric spike which is covered with long spreading awns. Spikelets many, sessile, alternate, 
at each joint of the articulated rachis, 1-5-flowered. Scales 3-7, the 2 lower empty, rarely 
entire, usually 2-many-cleft, the divisions linear and long-awned, the awns spreading, the 
flowering scales broader, acute, entire and long-awned, or 2-toothed and the teeth sometimes 
short-awned ; palet sliorter than the scale, 2-keeled. Stamens 3. Styles very short, dis- 
tinct. 

1, Sitanion longifolium J. G. Smith. Stems 3-5 dm. tall, stout, glaucous : leaf- 
blades of the innovations 1.5-3 dm. long, involute, often as long as the stems, those on the 
stem 1-2 dm. long, 1-4 mm. Avide : spike 1-1.5 dm. long, rather loosely flowered, its base 
inclosed in the upper sheath : spikelets 2, or sometimes 3, at each node, the empty scales 
subulate-setaceous, divaricate, 6-8 cm. long; flowering scales 8-11 mm. long, rougli, 
each tipped with a stout rough awn 5-6.5 cm. long. 

In dry soil, Nebraska to Wyoming, Texas and Xevada. Summer. 

119. ELYMUS L. 

Usually tall perennial grasses, with flat or convolute often rigid leaf -blades and a 
terminal cylindric dense spike which is sometimes interrupted and usually covered with 
long awns. Spikelets numerous, sessile, crowded, usually in alternate pairs, sometimes in 
3's or more, at each node of the continuous rachis, 2-several-flowered (rarely 1-flowered). 
Scales 4-sevcral (rarely 3), the 2 lower empty, rigid, awn-like, subulate, or linear, persis- 
tent, awn-pointed or awned, those at each node forming an apparent involucre, the flower- 
ing scales shorter, oblong to lanceolate, rounded on the back, obtuse or acute, usually 
awned, rarely awnless, the remaining scales if any smaller and empty ; palet shorter than 
the scale, 2-keeled. Stamens 3. Styles very short, distinct. Stigmas plumose. Lyme 

Gra3.s. Wili> Eye. 

Empty scales narrowly awl-shaped : spike slender. 1. E, striatum. 

Empty scales linear-lanceolate to linear : spike stout. 
Flowering scales glabrous. 
Flowering scales appressed-pubescent, usually densely so. 

Emptv scales linear, thick, firm, each bearing generally an awn much 

shorter than the body. 
Empty scales narrowly lanceolate, rather thin, each bearing commonly an 

awn equalling or exceeding the body. 
Spike rather loosely flowered, nodding at the summit, usually long- 

exserted. 



2. E. Virginicus. 



3. E. far sntlgl't mitt. 



Canadensis. 



Spike densely flowered, compact, strict, usually included at the base. 5. E. robustus. 



IGO 



POACEAE 



1. Elymus striktus Willd. Stems 3-9 dm. tall : leaf-sheaths glabrouB or hinsute ; 
blades 1-2.5 dm. long, 4-10 mm. wide, pubescent above : spike 6-12 cm. long, oft^n nod- 
ding, slender : spikelets 1-3-flowered, the empty scales 2-2.5 cm. long, including the slen- 
der rough awn, 1-3-nerved, the nerves, and often the whole scale, rough, hispid or hirsute, 
the flowering scales about 6 mm. long, hispid or liispidulous, each bearing a slender awn 
1.5-3 cm. long. 

In woods and on Lanks, Maine and Ontario to Tennessee, Xebraska and Kansas. Summer. 

2. Elymus Virginicus L. Stems 6-9 dm, tall : leaf-sheaths sometimes pubescent, 
the uppermost usually inflated and enclosing the base of the spike : blades 1-3.5 dm. long, 
4-16 mm. wide, rough : spike 5-18 cm. long, broad, stout, upright ; spikelets 2-3-fiowered, 
the empty scales very thick and rigid, lanceolate, 1.5-2.5 cm. long, including the short 
awn, 5-7-nerved, the flowering scales 6-8 mm. long, each bearing a rough awn 4-18 mm. 
long, or rarely awnless. 

In moist soil, especiallj' along streams, Xova Scotia and New Brunswick to Manitoba, Florida and 
Texas. Summer, 

3. Elymus hirsuHglumis Scribn. & Sm, Stems 3-9 dm. tall, erect: leaf-sheatlis 
longer than the internodes, the uppermost often inflated and enclosing the base of the spike ; 
blades 2-3 dm. long, 8-18 mm. wide, very rough on both surfaces : spike 6-15 cm. long, 
stout, the rachis pubescent : spikelets crowded in pairs, 2-5-flowered, the empty scalCvS 
linear, 10-12 mm. long, thick, 3-5-nerved, the nerves hirsute, each acuminate into an awn 
as long as or shorter than the body of the scale, the flowering scales lanceolate, 8-10 mm. 
long, each acuminate into a rough aAvn 12-16 mm. long. 

On river banks, Maine to North Carolina, Illinois and Nebraska, Summer. 

4. Elymus Canadensis L. Stems 6-15 dm. tall : leaf-blades 1-3 dm. long or more^ 
4-20 mm, wide, rough, sometimes glaucous : spike 1-3 dm, long, nodding, its peduncle 
usually much exserted : spikelets 3-5-flowered, the empty scales awl-shuped, I'igid, 3-5- 
nerved, 16-32 mm. long, including the slender rough long awn, the flowering scales 8-14 
mm, long, nearly glabrous to hirsute and each bearing a slender rough awn 2-5 cm. long. 

On river banks, Nova Scotia and New Brunswick to Alberta, Georgia, Texas and New Mexico- 
Summer. 

5. Elymus robustus Scribn. & Sm. Stems 9-12 dm. tall, erect, stout: leaf-blades 
firm, rough on both surfaces, 1-4 dm. long, 8-20 mm. wide : spike usually partially in- 
cluded at the base, stout, strict, 1-2.5 dm. long, compact : spikelets numerous, crowded, in 
2^s-4's, 3-4-flowered, the empty scales 10-12 mm. long, each bearing an awn about twice as 
long, the flowering scales lanceolate, 10-12 mm. long, from sparsely to densely appressed- 
pubescent, each bearing an awn 3-4,5 cm. long. 

On river banks, Illinois to Arkansas, Montana and Kansas. Summer. 



120. HYSTRIX Moench. 

Usually tall grasses, with simple stems, flat leaf-blades and terminal spikes. Spikelets 
numerous, at length spreading, 2-several-flowered, usually in pairs, rarely in 3*s, sessile, 
the clusters alternate on opposite sides of the continuous rachis, the rachilla articulated 
below the flowering scales. Scales 2-several, the 2 lower empty, subulate, wanting in all 
but the lowest spikelets, the flowering scales lanceolate, rigid, convolute, rounded on the 
back, the nerves confluent into the long awn ; palet somewhat shorter than the scale, 2- 



keeled. Stamens 3. Styles very short, distinct. Stigmas plumose. Grain oblong, ad- 
herent to the palet when dry. * 

1. Hyatrix Hystrix (L, ) Millsp. Stems 6-12 dm. tall: leaf-blades 1-2.5 dm. long, 
6-12 mm. wide, rough above : spike 7-18 cm. long : spikelets at length widely spreading, 
8-12 mm. long, exclusive of the awn, readily deciduous, the empty scales present only some- 
times in the lowest spikelets, the floAvering scales 8-12 mm. long, each acuminate into an 
awn about 2,5 cm, long. \_AspreUa Hystrix (L. ) Willd.] 

In rocky woods, New Brunswick to Ontario and Minnesota, Georgia, Illinois and Nebraska. Sum- 
mer. BOTTLE-BUUSH. 

121. ARUNDINARIA Michx. 

Tall shrubs, or rarely trees, with simple or branched stems, flat short-petioled leaf- 
blades w^hich are articulated to the sheath, and racemose or paniculate inflorescence. 
Spikelets large, compressed, 2-many-flowered. Scales 3-many, the 2 lower empty, unequal, 
the first smaller or sometimes wanting, the flowering scales longer, membranous, many- 
nerved, at the apex obtuse, acuminate or with a short awn or mucronate ; palet scarcely 



d 
I 



CYPEEACEAE 



161 



shorter than the scale, prominently 2-keelecl, Lodicules 3. Stamens 3. Styles 2 or 3, 
somewhat united at the base. Stigmas long, loosely plumose. 



Spikelets borne on radical shoots of the year : stems 4 m. tall or less. 
Spikelets borne on the old stems which are 5 m. tall or more. 



1, A, tecta. 

2. A, macrosperma , 



1. Anindinaiia t6cta (Walt.) Muhl. Stems 1-4 m. tall, erect, shrubby, branching 
at the summit : leaf-sheaths smootli or rough, ciliate on the margin ; ligule bristly ; blades 
lanceolate, 8-20 cm. long, 8-24 mm, wide, flat, more or less pubescent beneath, glabrous 
above: inflorescence borne on short leafless stems : spikelets 7-10-flowered, 2.5-4 cm. long, 
on pedicels 2,5 cm. long or less, the first scale sometimes wanting, the flowering scales 1-2 
cm. long, acute or acuminate, glabrous or pubescent. 

In swamps and moist soil, Maryland to Indiana, Missouri, Florida and Texas. Spring: and sum- 
mer. This and the following species flower only at intervals of several or many years. Reed. 

2. Arundinaria macrosp^rma Michx. Stems woody, 5-9 m. tall, finally branched 
above : leaf -sheaths ciliate on the margin ; blades lanceolate, 3 dm. long or less, the larger 
2-3 cm. Avide, those on the ultimate divisions smaller and crowded at the summit of the 
branches : spikelets 3.5-6 cm. long, on slender more or less leafy branches, the flowering 
scales glabrous and pubescent, acuminate. 

Along river banks and swamps, forming '* cane brakes," Virginia to Florida and Louisiana, and 
along the Mississippi River and its tributaries as far north as Kentucky, Tennessee and Missouri. Spring 
and summer. Cane. Cane Keed. 



/ 



Family 2. CYPERAOEAE J. St. Hil.' Sedge Family. 

Grass-like or rush-like caulescent or scapose herbs, many species perennial 
by long rootstocks. Stems or scapes (culms) slender, solid or rarely hollow, tri- 
angular, quadrangular, terete or flattened. Leaves 3-ranked, with closed 
sheaths : blades narrow. Flowers perfect or imperfect, arranged in spikelets, 
one (rarely 2) in the axil of each scale (glume, bract), the spikelets solitary or 
clustered, 1-many-flowered. Scales 2-ranked or spirally imbricated^ persistent 
or deciduous. Perianth hypogynous, composed of bristles, or scale-like parts, 



rarely calyx-like, or entirely wanting. 

Filaments slender or filiform. 



more. 



Ovary 1-celled. 



united carpels, 

less united. Ovule anatropous, erect. 



Androecium of 1-3 stamens, or rarely 

Anthers 2-celled. Gynoecium of 2-3 

Styles or stigmas 2-3, the former often more or 

Fruit a lenticular, plano-convex, or 



3-angled achene. Endosperm mealy. Embryo minute. 

Flowers of the spikelets, or at least one of them, perfect. 

Scales of the spikelets enclosing a bractlet or a pair of bractlets. 
Bractlets 2, convolute around the ovary. 
Bractlet solitary, minute, posterior. 
Scales of the spikelets not enclosing: bractlets. 

Spikelets perfect or mainly so, rarely of 2 scales and 1 flower, or if polyga- 
mous, plants withieaves not densely imbricated on the stems {Kyllinga). 
Scales of the spikelets 2-ranked. 

Perianth present, the members bristle-like. 
Perianth wanting. 

Spikelets with 2-severaI perfect flowers : scales several-many. 
Spikelets with 1 perfect flower : scales 2-4. 
Scales of the spikelets spirally imbricated all around. 

Base of the style not at all or only slightly thickened, deciduous. 
Perianth-parts conspicuously elongated. 
Perianth-parts not conspicuously elongated. 

Scales pubescent : perianth of bristles and dilated scales. 
Scales glabrous : perianth of bristles only or none. 
Base of the style manifestly swollen, persistent as a tubercle on the 
achene, or deciduous. 

Perianth present. 

Spikelets in compound umbels. 1-flowered. 

Spikelets solitary, several-many-flowered. 
Perianth wanting. 

Achene not surmounted by a tubercle. 

Achene surmounted by a tubercle. 

Spikelets in umbels or cymes, without an imbricated involucre. 
Spikelets in ai;erminal umbel : base of the style persistent. 
Spikelets in terminal and axillary compound cymes: most 
of the style persistent. 
Spikelets in heads subtended by an imbricated involucre. 
Spikelets polygamous, or rarely of 4 scales and only 1 flower. 
Scales of the spikelets 2-rariked. 
Scales of the spikelets of spirally imbricated scales. 

Perianth present. 



1. LirOCARPHA. 

2. Hemicarpha. 



3. dulichium. 

4. Cypertjs. 

5. Kyllinga. 



6. Eriophorum 

7. Fuirena, 

8. SCIBPUS. 



9. Websteria. 
10. Eleocharis. 

11. FlMBKISTYLlS. 



12. Stenophyllus 

13. psilocarya. 

14. DiCHROMENA. 

15. Abildgaardia, 

16. schoexus, 



^ Prepared with the assistance of Dr. Nathaniel Lord Britten. 
11 



j^ 



162 



CYPERACEAE 



17. CLADTirM. 

18. Kemtkea. 

19. Rykchospora 



Perianth wanting. 

Stigmas 3 : style deciduous. 
Inflorescence paniculate : 
Inflorescence capitate : 
Stigmas 2 : style persistent. 
Flowers monoecious or dioecious. 

Aclienes not enclosed in a utricle (perigA^nium): 20. Scleria. 

Achenes enclosed in a utricle (perigynium): 21. Carex. 

1. LIPOCARPHA E. Br. 

Low annual slender herbs, with tufted scapes, and terete many-flowered spikelets in a 
terminal liead, subtended by an involucre of 1-several bracts. Scales firm, spirally imbri- 
cated, all fertile or several of the lower ones empty, at length deciduous, each enclosing 2 
bructlets which are convolute around the ovary. Flowers perfect. Perianth wanting. 
Stamens 1-2. Style deciduous, its base not swollen. Stigmas 2-3. Achene plano-convex 
or 3-angled. 

1. Lipocarpha maculata (Michx, ) Torr. Glabrous. Scape grooved, compressed, 
smooth, longer than the narroAvly linear somewhat channeled leaf-blades, 7-25 cm^. tall : 
bracts of the involucre 2-4: spikelets ovoid-oblong, obtuse, 5-6 mm. long, 2 mm. thick, in 
a terminal capitate cluster : scales rhombic or lanceolate, acute, curved, the sides nearly 
white, or flecked with reddish brown spots : exterior bractlet convolute ^around the achene, 
nerved, hyaline : stamen 1 : acliene oblong, yellowish, contracted at the base. 

In wet or moist soil, eastern Virginia to Florida. Also adventive farther north. Summer and fall. 

2. HEMICARPHA Nees & Am. 

Low tufted mostly annual caulescent herbs, with erect or spreading, almost filiform 
stems and leaves, and terete small terminal capitate or solitary spikelets subtended by an in- 
volucre of 1-3 bracts. Scales spirally imbricated, deciduous, each subtending perfect 
flowers and a single posterior bractlet. Perianth wanting. Stamens 1-3. Style deciduous, 
not swollen at the base. Stigmas 2. Achene oblong, turgid or lenticular. 

1. Hemicarpha miciantha (Vahl) Britton. Annual, glabrous. Stems compressed, 
grooved, 2-10 cm. long, mostly longer than the setaceous smooth leaf-blades : spikelets 
ovoid, many-flowered, obtuse, about 2 mm. long: involucral bracts usually much exceed- 
ing the spikelets : scales of the spikelets brown, obovate, each with a short blunt spreading 
or recurved tip : stamen 1 ; achene obovoid-oblong, obtuse, mucronulate, little compressed, 
light brown. 

In moist, sandy soil, Rhode Island to Pennsylvania, Iowa and Nebraska, Florida, Texas and Mex- 
ico. Summer and fall. — A variety ranging from Kansas to Texas, H. micrantha aristtddta Coville, has 
pale cuneate-obovate scales each tapering into a squarrose awn about as long as the body. 

3. DULICHIUM L. C. Eich. 

Tall perennial herbs, with terete hollow, conspicuously jointed stems, leafy to the top, 
the lower leaves reduced to sheaths. Spikes axillary, peduncled, simple or compound. 

■m 

Spikelets 2 ranked, flat, linear, falling away from the axis at maturity (?), many-flowered. 
Scales 2-ranked, carinate, conduplicate, decurrent on the joint below. Flowers perfect. 



Perianth of 6-9 retrorsely barbed bristles. Stamens 3. Style persistent as a beak on the 

summit of the achenes. Stigmas 2. Achenes linear-oblong. 

1. Dulichiuin anindinaceum (L. ) Britton. Stems stout, 3-10 dm. tall, erect : 
leaves numerous : blades flat, 2-8 cm. long, 4-8 mm. wide, spreading or ascending, the 
lower sheaths bladeless, brown toward their summits ; peduncles 4-25 mm. long : spike- 
lets narrowly linear, spreading, 1-2.5 cm. long, about 2 mm. wide, 6-12-flowered ; scale 
lanceolate, acuminate, strongly several-nerved, appressed, brownish : bristles rigid, longer 
than the achene : style long-exserted, persistent. [Z>. spatkaceum (L. ) Pers.] 

In wet or muddy places, Kova ^Scotia to Ontario, Minnesota and Nebraska, Florida and Texas- 
Summer and fall. 

4, CYPERUS L. 

Annual or perennial scapose herbs. Leaves basal : blades narrow. Scapes, in our 
species simple, triangular, and with one or more bracts at the summit forming an invo- 
lucre to the simple or compound, umbellate or capitate inflorescence. Eays of the umbel 
sheathed at the base, usually very unequal, one or more of the heads or spikes commonly 
sessile. Spikelets flat or nearly terete, the scales falling away from the rachis as they ma- 



4 

i 



CYrERACEAE 



163 



1. C. flavescens. 



2. C. diandrus. 



3. 
4. 
5. 



C. rivularis. 
C. helvus. 
C, hipartltus. 



6. C. NuttalUL 

7. C microdontus^ 



8. 

10. 

11. 
12. 

13. 
14. 



C. GatcnL 

C, polystachyus, 

C. pumilus, 

C. flavicomus. 
C. Hochstetteri, 

C, laevigatus, 
C, Carcyi. 



15. 
16. 



C. inflcxus, 
C * squarrosu8. 



ture or persistent and the spikelets falling away from the axis of the head or spike with 
the scales attached. Scales concave, conduplicate or keeled, 2-ranked, all flower-bearing 
or the lower ones empty. Flowers perfect. Perianth none. Stamens 1-3. Style de- 
ciduous from the summit of the achene. Stigmas 2-3. Achene destitute of a tubercle. 

Style-branches or stigmas 2 : achene lenticular. 
Achene laterally compressed. 

Superficial cells of the achene oblong. 
Superlicial cells of the achene quadrate. 

Aehenes oblong, linear or narrowly obovoid : plants relatively low. 
Scales of the spikelets blunt. 

Spikelets several in each umbel. 

Scales membranous, dull : style-branches or stigmas much ex- 
serted. 

Scales subcoriaceous, shining : style-branches or stigmas included 
or scarcely exserted. 
Spikelets 8-20 mm. long, dark green to brown. 
Spikelets o~S mm. long, yellowish green or straw-colored. 
Spikelet solitary, appearing lateral. 
Scales of the spikelets acute or mucronate. 
Scales merely acute. 

Achene narrowlv obovoid. 
Achene linear to linear-oblong. 
Scales ovate : umbel subcapitate. 

Scales oblong-lanceolate : umbel-rays usually developed. 
Scales 2-^2.5 mm. long, chestnut-brown, shining. 
Scales 1.5 mm. long, gray-brown or straw-colored, dull. 
Scales sharply mucronate. 
Achenes broadly obovoid to orbicular : plants relatively tall. 
Achenes obovoid, nearly as long as the scales. 
Achenes obovoid-orbicular, much shorter than the scales. 
Achene dorsally compressed. 

Spikelets few, appearing lateral : one involucral bract long and erect. 
Spikelets numerous, capitate: involucral bracts sei^eral and spreading. 
St vie -branches or stigmas 3 : achene trigonous. 

A. Scales falling away from the persistent rachis of the flattened spikelets. 
a. Wings of the rachis, if any, permanently attached to it. 
Scales tipped with recurved awns : low annuals. 

Achene 1 mm. long, narrowly obovoid : scales light brown. 
Achene 0.5 mm. long, broadly obovoid : scales chestnut-brown. 
Scales obtuse, acute or acuminate, not awn-tipped, 
AVings of the rachis none, or \ery narrow. 

Scales of the spikelets appressed, closely contiguous. 
Stamens 3 or 1 : scales ovate, oblong or lanceolate. 
Stamens 3 : spikelets linear to linear-oblong. 
Leaves not viscid. 

Scales acuminate : plants annual. 
Scales obtuse or mucronate : plants perennial. 
Scales obtuse : achene obovoid. 

Scales mucronate : achene oblong. 
Leaves viscid. 
Stamen 1 : spikelets ovate to lanceolate. 
Scale-tips recurved. 

Annual : achene broadly oblong. 
Perennial : achene narrowly oblong or elliptic. 
Scale-tip)s straight or very nearly so : plants perennial, 
Spikelets lanceolate to oblong-lanceolate. 
Achene linear-oblong, stipitate. 
Achene ovoid, not stipitate. 
Spikelets ovate, elongating in fruit. 

Leaves, at least at the base, strongly transverse-veined 
between the nerves. 
Leaf-blades 6-12 mm. wide : spikelets 6-14 mm, 

long. 
Leaf-blades 2-6 mm. wide : spikelets 4-6 mm. long. 
Leaves not transversely veined between the nerves. 
Spikelets yellow, blunt. 
Spikelets red or reddish brown, acute. 
Stamens 2 : scales nearly orbicular or obovate, mucronulate. 
Scales of the spikelets not appressed, distant. 
Spikelets linear-filiform, spicate. 
Spikelets merely linear or oblong-linear, densely capitate. 

Wings of the rachis distinct. 

Scapes not transversely septate, 3-angled. 

Leaves reduced to pointed sheaths. 

Leaves with elongated linear blades. 

Scales mucronate. 

Scales not mucronate. 

Spikelets 3-4 mm. wide. 

Spikelets 1.5-2 mm. wide. 

Scales wholly or partially purple-brown : achene linear 

oblong.' 
Scales tightly appressed throughout. 

Scales with free tips. 
Scales straw-colored : achene obovoid. 

Scapes transversely septate, terete. 



17. C. compressus. 



18. 
19. 
20. 



C, Biickleyi, 
C. Bui^hiu 
C. elegans. 



21. 
22. 



C. acuminatus, 
C. cyrtolepis. 



23. 

24. 



C. Drummondh. 
C ochraceus. 



25. 

26. 

27. 
28, 
29. 



30. 
31. 



C. virens. 

C, pseudovegetus. 

C. Surinamensis, 
C\ reflexus, 
C. Ina, 

C, distans. 

C. cephalanthus . 



32. C, Haspan, 

33. C dentatus, 

34. C muUiradiatxu. 



35. 
36. 
37. 

38. 



(7. rotundas. 

a Ham. 

C, esculcntus, 
C. articulatus. 



/ 



164 



CYPERACEAE 



b. Wings of the rachis separating from it as interior scales : annuals. 
Spikes loose, or if dense not narrow]}' cylindric : spikelets 6-25 mm. long. 
Spikelets crowded : scales loose. 
Spikelets not crowded : scales closely appressed. 
Spikes very dense, cj^lindric : spikelets 3-5 mm. long. 
B. Eachis of the spikelets deciduous. 

Rachis breaking up into l-fruited joints : spikelets nearly terete. 
Spikes solitary : scapes filiform : plants perennial. 
Spikes umbellate or capitate-congested : scapes stout to slender : 
plants annual. 
Scales of the spikelets distant : achene linear-oblong. 
Scales of the spikelets manifestly imbricated : achene obovoid. 
Spikelets relatively loosely spicate. 

Spikes dull brown : scales thin, not tightly appressed. 
Spikes yellowish or grayish brown : scales firm, appressed. 
Spikelets densely congested into 1-4 heads. 

Inflorescence umbellate: spikes disposed at the ends of the 2-4 

rays of the umbel. 
Inflorescence capitate : spikes collected into a terminal con- 
gested cluster. 
Rachis deciduous above the lower pair of scales : plants perennial by hard 
corm-like tubers. 
Achene narrowly linear-oblong, 23^^ times as long as thick. 
Spikelets distinctly flattened, several-many-flowered. 
Spikelets in dense globular heads. 
Spikelets loosely spicate or relatively so. 
Spikelets chestnut-brown. 
Spikelets yellow to yellow-broAvn. 
Scales appressed. 
Scales loose, somewhat spreading. 
Spikelets nearly terete to a little flattened, 1-few-flowered. 
Spikelets loosely spicate. 

Spikelets 1-2 cm. long: achene abovit 3 mm. long. 
Spikelets less than 1 cm. long : achene 1.5 mm. long. 
Spikelets capitate or capitate-spicate. 

Spikelets all reflexed : scapes almost always rough. 
Spikelets spreading or only the lower ones reflexed : scapes 
smooth. 
Spikes or heads dense, cylindric to globose. 
Spikes globose. 
Spikes cylindric to oval or obovoid. 

Spikelets 3-7 mm. long : spikes obovoid or cylindric. 
Spikes obovoid: lower spikelets reflexed. 
Spikes cylindric. 

Spikes 0.5-2 cm. long, simple. 

Spikelets 3-4 mm. long, 1-2-flowered. 
Spikelets 5-7 mm. long, 3-4-flowered. 
Spikes 1.5-3.5 cm. long, usually compound. 
Spikelets 8-10 mm. long : spikes oval. 
Spikelets loosely spicate or capitate. 
Spikelets 8-12 mm. long, subulate. 
Spikelets 3-5 mm. long, not svibulate. 
Achene oblong to obovoid, not more than twice as long as thick. 
Spikelets Avith 1-4 achenes. 

Rachis wingless or narrowly winged. 

Umbel simple or head solitary : leaf-blades relatively narrow. 
Spikelets loosely spicate. 
Spikelets densely spicate or capitate. 
Heads ovoid to cylindric. 
Heads globose to subglobose. 

Heads dark brown : scales mucronulate. 
Heads green or greenish brown : scales not mu- 
cronulate. 
Achene 2 mm. long : scales about 2 mm. long. 
Achene 1 mm. long : scales less than 2 mm. 
long. 

Umbel compound : leaf-blades relatively broad. 
Rachis- wings broad, membranous. 

Scales firm, not appressed. 

Scales thin, closely appressed. 
Spikelets with 5-10 achenes. 

Heads sessile, or on rays less than 2 cm. long. 
Heads terminating rays 2-7 cm, long. 



39. C. eryfhrorhizos. 

40. C. digitalus. 

41. a Hald. 



42. C, Floridanus, 



4.^ 



o. 



C. EngelmanniL 



44. 
45. 



C. speciosus, 
C. ferax. 



46. C. Eggersii. 

47. C\ oxycarioides. 



48- C. MartindalcL 
49. C. sctigeriis. 



50. 
51. 



C. strigosus. 
C. stenolepU. 



52. 
53. 



C refractus. 
C, dissitiflorus. 



54. C. retwfradus. 



55. (7. ovularis. 



56. C retrorsus. 



57. C. cylindricus. 

58. C. MankiL 

59. C. cylindrostachys. 

60. C. Lancastriensis, 

61. C, uniflorus. 

62. C. suhuniflorus. 



63. C. tetragonus, 

64. C.flavus. 

65. C.fuligineus. 



66. CfiUculmu. 

67. C. BlodgettiL 

68. (7. ligulaHs, 

69. C. GrayL 

70. (7. echinatus, 

71. C hrunneus, 

72. C. Ottonis. 



I 

J 



J 
,1 



1. Cyperus flav6scens L, Annual, yellowish green. Leaf-blades 2-3 mm. wide, 
smooth, the longer usually exceeding the inflorescence : scapes very slender, tufted, 7-30 
cm. tall : spikelets in 3's-6's, linear, subacute, yellow, many-flowered, flat, 8-18 mm. long, 
3-4 mm. broad ; the clusters terminal and sessile, or on 1-4 short rays : scales ovate, ob- 
tuse, 1 -nerved, appressed, twice as long as the achene: stigmas 2: achenes orbicular-obo- 
void, black, obtuse, shining, the superficial cells oblong. 

In marshy soil, Maine to Michigan, Florida and Mexico. Also in the Old \yorld. Summer and fall . 

2- Cyperus diindnis Torr. Annual, deep green. Leaf-blades about 2 mm. wide : 
scapes tufted, slender, 5-40 cm. tall : bracts of the involucre usually 3 : spikelets 8-18 
mm. long, linear-oblong, acute, flat, many-flowered ; the clusters sessile and terminal or at 



CYPERACEAE 



165 



the ends of 1-3 rays : scales ovate, green, brown, or with brown margins, obtuse, 1-nerved, 
appressed, membranous, dull : stigmas or style-branches 2, much exserted : achenes len- 
ticular, oblong, gray, not shining, J as long as the scale, its superficial cells quadrate and 
about as long as Avide, as in the eleven following species. 

In marshy places, New Brunswick to Minnesota, South Carolina and Kansas. Summer and fall. 

3. Cyperus rivularis Kunth. Similar to the next preceding species. Scapes slender, 
tufted : umbel usually simple: spikelets linear or linear-oblong, acutish, 8-20 mm. long : 
scales dark green or brown, or with brown margins, appressed, firm, rather coriaceous, 
shining, obtuse : stigmas or style-branches 2, scarcely exserted : achenes oblong or oblong- 
obovoid, lenticular, somewhat pointed, dull. 

In wet soil, especially along streams and ponds, Maine to Ontario, Michigan, Nebraska, North 
Carolina and Missouri. Summer and fall. 

4. Cyperus Mlvus Liebm, Annual. Leaves generally 2 or 4 ; blades 1-3 mm. 
wide, smooth : scapes tufted, 1-7 dm. tall, as long as the leaves or longer : bracts of the 
involucre narrower than the leaf-blades, surpassing the umbel, the longer ones 5-20 cm, 
long : umbel capitate, or 2-4 rays becoming 1-3 cm. long : spikelets few, linear to linear- 
lanceolate, 6-8 mm. long, acutish: scales straw-colored or yellowish green, ovate, obtuse, 2 
mm.^ long, deciduous at maturity, 2-keeled on the back : styles 2, well united : achenes 
lenticular, oval or oval-obovoid, 1 ram. long, brown, dull, barely ^ as long as the scale. 

In ditches and moist grounds, Louisiana and Texas ; also through the tropics to eastern South 
America and in the West Indies. Spring to fall. 

5. Cyperus bipartitus Torr. Annual. Leaves usually 2 at the base of the the scape ; 
blades setaceous or filiform : scapes 5-15 cm. tall : bracts of the involucre solitary or 2, but 
only one well developed and erect : spikelet ovate-oblong, 5-7 mm. long, rather obtuse, 
about 14-flowered : scales ovate, obtuse, somewhat coriaceous, closely imbricated : styles 2, 
nearly distinct : achenes lenticular, obovoid, fully 1 mm. long, obtuse. 

In sandy soil, near New Orleans, Louisiana. Summer. 

6. Cyperus Nutteillii Eddy. Annual. Scapes slender, tufted, equalling or longer 
than the leaves : bracts of the involucre 3-5, spreading, the larger often 12 cm. long : um- 
bel 3-7- rayed : spikelets rather loosely clustered, linear, very acute, flat, spreading, 1-3 
cm. long, 2-3 mm. wide : scales yellowish brown except the green keel, oblong, acute : 
stigmas 2, somewhat exserted : achenes lenticular, narrowly obovoid, obtuse or truncate, 
dull, light brown, J to ^ as long as the scale. 

In salt marshes, or drifting sand, coast of Maine to Florida and Mississippi. Summer and fall. 

7. Cyperus microddntus Torr. Annual. Leaf-blades about 2 mm. wide : scapes 
very slender, tufted, sometimes 0.5-1 dm. high : bracts of the involucre much elongated : 
umbel commonly simple, sessile, subcapitate : spikelets linear, acute, 6-18 mm, long, less 
than 2 mm. wide, yellowish brown : scales ovate, barely 2 mm. long, acute, thin becoming 
rather lax : stigmas 2, much exserted : achenes lenticular, linear-oblong, short-pointed, 
light brown, ^ as long as the scale. 

In wet soil, on or near the coast, Virginia and North Carolina. Summer and fall. 

8. Cyperus Gat^sii Torr. Annual, bright green. Leaves often 3-6; blades 1-4 mm. 
wide, or sometimes narrower or even filiform, not firm : scapes slender, tufted, 1-4 dm. 
tall, often surpassing the leaves : bracts of the involucre 3-5, surpassing the umbel, the 
longer ones usually 10-20 cm. long : umbel with 3-8 rays 1-5 cm. long, or rarely nearly 
capitate: spikelets few, linear or linear-lanceolate, 6-15 mm. long, acute : scales light chest- 
nut-brown, oblong-lanceolate, 2-2.5 mm. long, shining, striate, deciduous at maturity: 
achenes oblong, fully 1 mm. long, grayish, abruptly apiculate, fully i as long aa the scale. 

In springy places and low grounds, Virginia to Florida and Texas. Spring to fall. 

9. Cyperus polystdchyus Eottb. Annual, pale green. Leaves usually 4-8 ; blades 
narrowly linear, 2-4 mm. wide, smooth like the scape : scapes tufted, slender, 1-9 dm. 
tall, generally surpassing the leaves : bracts of the involucre 3-5, much longer than the 
umbel, nearly equal in length, or one or tAV^o sometimes 1-2 dm. long : umbel capitate or 
some of the rays becoming 1-3 cm. long : spikelets numerous, linear-lanceolate, 6-20 mm. 
long, acute, 15-25-flowered : scales 1.5 mm. long, gray-brown or straw-colored, acute, dull, 
deciduous at maturity : achenes lenticular, oblong, 1.2 mm. long, dull, about twice as long 
as thick, grayish. 

In ditches and low grounds, Florida to Louisiana, and in tropical America. Spring to fall. 

10. Cyperus pumilus L. Annual, pale green. Leaves often 3-4 ; blades gradually 
narrowed to the apex : scapes densely tufted, slender, 1-3 dm. tall, or sometimes shorter, 
mostly as long as the leaves or longer : bracts of the involucre usually 3 or 4, 1 or 2 of 
them much longer than the others, the longest one often 10 cm. in length : umbel mnch 
shorter than the involucre, with 3-9 rays, 1-6 cm. long and a sessile cluster of spikes, or 
sometimes all spikes sessile : spikelets linear, 4-8 mm. long, relatively few in a spike, 15- 



166 



CYPERACEAE 



25-flowered: scales silvery green, 1.5 mm. long, 3-toothcd at the apex, the middle tooth 
longest and acuminate, thus forming a sharp mucro, with broad scarious margins : achenes 
about 0.5 mm. long, obovoid, truncate at the top, barely l as long as the scale. 

In sandy soil, Florida and Alabama. Common in the tropics. Summer. 

11. Cypenis flavicomus Michx. Annual, Leaves 4-6 mm. wide : scapes 3-10 dm. 
tall : bracts of the involucre 3-8, the longer ones much exceeding the inflorescence : um- 
bels few-several -rayed, often compound ; primary rays 1-6 cm, long : spikelets numerous, 
usually densely clustered, linear, acute, 8-20 cm. long, 2-3 mm. wide, flat, many-flowered, 
spreading : scales oblong, obtuse, thin, dull yellowish brown : stigmas 2, little exserted : 
achenes obovoid, lenticular, black, mucronate, not shining, nearly as long as the scales and 
often persistent on the rachis after these have fallen away. 

In wet or moist sandy soil, Virginia to Florida and Louisiana. Summer and fall. 

12. Cyperus Hochst6tteri Nees. Annual, bright green. Leaves mostly 2 or 3 ; 
blades 2-4 mm. wide, smooth like the scape: scapes tufted, relatively stout, 1.5-6 dm, 
tall, mostly overtopping the leaves : bracts of the involucre 3-5, all, or only the longer ones 
surpassing the umbel, longer ones 10-20 cm. long : umbel with 2-5 rays, 1-10 cm. long 
and one or more spikes sessile in the involucre : spikelets linear or linear-lanceolate, 1-4 
cm. long, 12-54-flowered : scales broadly ovate, deep chestnut color, 2 mm. long, rather 
blunt: achenes lenticular, obliquely obovoid-orbicular, 1.5 mm. long, about J as long as 
the scale, apiculate, deep brown. 

In low grounds, Louisiana, Texas and New Mexico. Also in the tropics. Spring to fall. 

13. Cyperus laevig^tus L, Perennial, light green, resembling species of Scirpus. 
Leaves reduced to several colored scales at the base of the scape, the upper ones sometimes 
prolonged into short blades: scapes tufted from horizontal rootstocks, 0.5-4 dm. tall, 
smooth : spikelets few, usually 3-6 in a head at the top of the scape, subtended by the 
single conspicuous erect involucral bract, oblong-ovate to linear, 6-15 mm. long, rather 
obtuse, mostly 16-30-flowered : scales deltoid-ovate, blunt, nearly 2 mm. long, deep chest- 
nut-brown and lustrous or merely variegated with chestnut, deciduous at maturity : achenes 
1.5 mm. to nearly 2 mm. long, elliptic or obovoid-elliptic, minutely pointed. 

In sandy soil, South Carolina and California. Also circumtropical. Spring to fall, 

14. Cyperus Careyi Britton. Annual, pale green. Leaves several ; blades 1-1.5 
mm. wide, keeled : scapes tufted, slender, less than 1 dm. tall, surpassed by some of the 
leaves, densely lejify at the base : bracts of the involucre usually 3, surpassing the umbel, 
2-8 cm. long : umbel capitate, about 1 cm. broad, sessile : spikelets crowded, numerous, 
oblong or ovate-oblong, 3-4 mm. long : scales silvery or whitish, about 2 mm. long, broadly 
ovate, abruptly pointed, delicately ribbed : stigmas 2 : achene lenticulai', oblong. 

In sand, middle Florida. Summer. 

15. Cyperus infl6xu3 Muhl. Annual, fragrant in drying. Leaf-blades 2 mm. Avide 
or less : scapes slender or almost filiform, tufted, about equalled by the leaves : bracts of 
the involucre 2-3, exceeding the umbel : umbel sessile, capitate, or 1-3-rayed : spikelets 
linear-oblong, 6-10-flowered, 4-6 mm. long : scales light brown, lanceolate, rather firm, 
strongly several-nerved, each tapering into a long, recurved awri : stigmas 3 : achene 3- 
angled , narrowly obovoid, 1 mm. long, obtuse, mucronulate, brown, dull. 

In wet, sandy soil, Vermont to the Northwest Territory, Oregon, Florida, Texas, California and 
Mexico. Summer. 

16. Cyperus squarrosus L. Annual, bright green, licorice-scented. Leaves few ; 
blades mostly 1 mm. wide or narrower, curved, revolute : scapes tufted, 2-15 cm. tall, 
slender, overtopped by some of the leaves : bracts of the involucre usually 3 or 4, surpass- 
ing the umbel, rarely 10 cm. long: umbel of 2-5 rays with one or more spikes sessile in 
the involucre, or sometimes all the spikes collected in a head : spikelets linear, 5-10 mm. 
long, few in a spike, many-flowered: scales light chestnut-colored, nearly 2 mm. long, the 
recurved spreading awn-like tip nearly as long as the body: achenes 3-angled, broadly obo- 
void, 0,5 mm. long, brown, mmutely apiculate. 

In sandy soil, Georgia and Florida to Texas and California. Also in the West Indies and tropics 
of the Old World. 

17. Cypenis compr^ssus L. Annual. Leaves light green; blades about 2 mm. 
wide : scapes slender, erect or reclining, smooth, 7-25 cm. long : bracts of the involucre 
2-3, the longer exceeding the spikelets : umbel capitate or with 2 — 3 short rays : spikelets 
narrowly lanceolate, acute, 8-20 mm. long, 3-4 mm. wide, very flat, manv-flowered : scales 
light green with a yellow band on each side, ovate, acuminate, firm, keeled, several-nerved : 
stigmas 3: achene sharply 3-angled, obovoid, obtase, dull brown, about J as long as the 
scale. 

In fields, Marj'land to Florida, Missouri and Texas. Also in tropical America and the Old World. 
Summer and fall. 



CYPERACEAE 



167 



18. Cyperua Buckleyi Britton. Perennial, bright green. Leaves several at the 
base of the scape ; blades 2-7 mm. wide, curling in age : scapes sometimes tufted, 3-15 dm. 
tall, overtopping the leaves, often conspicuously elongated : bracts of the involucre usually 
3-5, 10-20 cm. long or the smaller ones shorter : umbel of 3-8 rays varying from 1-12 cm. 
in length and one or more spikes sessile in the involucre: spikelets linear, 8-12 mm. long, 
rather lax : scales light or dark chestnut, rhombic-ovate, 3 mm. long, obtuse, with several 
prominent ribs, not crowded, spreading and deciduous in age : achenes 3-angled, obovoid, 
2 mm. long, brown. 

In river valleys, the Indian Territory and Texas to adjacent Mexico. Summer and fall. 

19. Cyperus Bushii Britton. Perennial by tuber-like corms. Leaves shorter than 
the scape, 4 mm. wide or less, smooth, not viscid: scapes slender, smootli, 3-6 dm. tall: 
bracts of the involucre 3-5, the longer mucli exceeding the umbel : umbel simple, 1-5-rayed, 
the rays mostly short, or spikes congested into a single cluster : spikelets loosely capitate, 
linear, compressed, acute, 8-16 mm. long, 11-15-flowered : scales firm, shining, oblong, 
mucronate, strongly about 11-nerved: stigmas 3 : acliene oblong, about 2 mm. long, nearly 
twice as long as thick, 3-angled, pale brown, apiculate, f as long as the scale. 

In sandy soil, Minnesota and Wisconsin to Nebraska and the Indian Territory. Summer. 

20. Cyperus 6Iegans L. Perennial, pale green. Leaves several at the base of the 
scape, viscid ; blades mostly 2-4 mm. broad, involute above the loose, striate sheaths : 
scapes tufted, 2-7 dm. tall, sometimes equalled by the leaves or overtopped by them : 
bracts of the involucre 3-5, very unequal, some 5 cm. long, others often 30 cm. long : 
umbel simple or compound, usually of 3-6 rays, 1-8 cm. long, with one or more spikes ses- 
sile in the involucre : spikelets linear-oblong, 6-12 mm. long, crowded : scales light tan- 
colored, rhombic-ovate, 3 mm. long, ascending, scabrous on the back, with more or less 
spreading short awn-like tips : achenes 3-angled, obovoid, fully 1.5 mm. long including the 
curved subulate beak. 

In sandy soil, Florida to Texas and New Mexico. Also in tropical America. Spring to fall. 

21. Cypenxa acuxninatus Torr. & Hook, Annual. Leaves light green ; blades 
usually less than 2 mm. wide : scapes very slender, tufted, 7-40 cm. tall : bracts of the in- 
volucre much elongated : umbel 1-4-rayed, simple, rays short : spikelets flat, ovate-oblong, 
obtuse, 4-8 mm. long, many-flowered, densely capitate : scales oblong, pale green, 3-nerved, 
coarsely cellular, condu plicate, each with a short sharp more or less recurved tip : stigmas 
3: achenes sharply 3-angled, gray, broadly oblong, narrowed at each end, little over' 0.5 
mm. long, about J as long as the scales. 



In moist soil, Illinois to Iowa, Oregon, Louisiana, Texas and California. Summer and fall. 

22. Cyperus cyrtdlepis Torr. & Hook. Perennial, bright green. Leaves mostly 
overtopped by the scape ; blades 3-4 mm. long, more or less revolute : scapes usually tufted, 
slender, 1-5 dm. long, smooth : bracts of the involucre 3-5, the longer ones surpassing the 
umbel, spreading : umbel capitate, or of 3-6 rays and some spikes sessile in the involucre, 
often compound : spikelets oblong or ovate-oblong, 5-7 mm. long, gray or yellowish, 16- 
24-flowered : scales ovate, barely 2 mm. long, acute, scarious-raargined, with short re- 
curved spreading tips : achenes 3-angled, elliptic or narrowly oblong, about 1 mm. long, 
acute or slightly pinched at both ends, rather lustrous. 

In swampy grounds, Arkansas to Arizona and Texas. Spring to fall. 

23. Cyperus Drummondii Torr. & Hook. Perennial. Leaves much shorter than 
the scape ; blades 4-6 mm. wide : scapes 8-12 dm, tall, its angles very sharp, or almost 
winged, scabrous : bracts of the involucre usually 2, surpassing the umbel : umbel capitate 
or congested, or with several more or less elongated rays, of many (40-50) spikelets : spike- 
lets lanceolate to oblong-lanceolate, 20-30-flowered, 6-12 mm. long, yellowish : scales lan- 
ceolate, very closely imbricated, acute : achenes 3-angled, linear-oblong, above the slender 
stipe. 

On plains or prairies, Texas. Summer. 

24. Cyperus ochriceus Vahl. Perennial, bright or yellowish green. Leaves over- 
topped by the scape ; blades mostly 2-6 mm. long, smooth : scapes solitary or tufted » rela- 
tively slender, 2-12 dm. tall, smooth : bracts of the involucres mostly 3-5, the longer ones 



much surpassing the umbel, spreading : umbel mostly compound, of 5-10 rays of v; 
lengths, rarely over 15 cm. long, and one or more spikes sessile in the involucre : spikelets 
linear-oblong to linear-lanceolate, 5-12 mm, long, 25-35-flowered : scales ovate, 2 mm, long, 
rather blunt : achenes ovoid, slightly pinched at both ends, not stipitate. 

In sandy soil, Alabama to Texas. Also in the West Indies and Mexico. Spring to fall. 

25. Cyperus virens Michx. Perennial, pale green. Leaves elongated ; blades 6-12 
mm, wide, striate : scapes stout, often tufted, 5-15 dm. tall, overtopping the leaves, smooth, 
naked above : bracts of the involucre 3-7, variable in length, the longer surpassing the 



f 



168 



CYPERACEAE 



umbel, sometimes becoming 6 dm. long: umbel mostly compound, of 3-12 rays varying 
from 1-20 cm. in length, with 1 or more spikes sessile in the involucre : spikelets numer- 
ous, ovate, 6-14 mm. long, acutish, many-flowered : scales oblong-ovate, fully 2 mm. long, 
red-brown, pinched at the ends. 

In sandy soil, North Carolina to Florida, and California, and in Mexico and Central America. 
Spring to fall. 

26. Cyperus pseudov^getns Steud. Perennial by thickened tuber-like joints of 
the rootstocks. Leaf-blades 2-6 mm. wide, smooth, nodulose, the midvein prominent : 
scapes rather stout, 3-13 dm. high, often equalled by the leaves : bracts of the involucre 
4-6, spreading : umbel several-rayed, compound : spikelets ovate, flat, many-flowered, light 
green, densely capitate, 4-6 mm. long : scales keeled, conduplicate, l-nerved, curved, acute : 
stigmas 3 : acliene linear, 3-angled, slightly stalked, [C calcaratus iS'ees. ] 

In marshes, Delaware to Kansas, Florida and Texas. Summer and fall. 

27. Cypervis Surinam^nsis Eottb. Perennial, pale green. Leaves overtopped by 
the scape ; blades mostly 1.5-4 mm. wide, usually rough along the margins : scapes slen- 
der, solitary or tufted, 2-12 dm. tall, naked and rough above: bracts of the involucre 
usually 3-5, one or all longer than the rays of the umbel, rough-margined : umbels mostly 
compound, of generally 8-12 rays of various lengths, several spikes sessile or clustered in 
the involucre : spikelets oblong or linear-oblong, 5-12 mm. long, yellow, blunt, 40-50- 
flowered, sometimes densely clustered: scales ovate, nearly 1.5 mm. long, deciduous in 
age : achenes 3-angIed, oblong, about 0.8 mm. long, brown, pinched at both ends. 

In sandy swatnps, Florida to Texas, and throughout tropical America, Spring to fall. 

28. Cypenis refl6xus Vahl. Perennial, bright green. Leaves overtopped by the 
scape ; blades 1-4 mm. broad, smooth : scapes often tufted, slender, 1-7 dm, tall, smooth : 
bracts of the involucre 3-5, one or more surpassing the umbel, often compound, of 2-5- 
rays and one or more spikes sessile in the involucre or capitate : spikelets ovate or ovate- 
lanceolate, 4-6 mm. long, red or reddish brown, 20-25-flowered ; scales ovate, about 1.5 
mm. long, acute, imbricated : achenes 3-angled, elliptic, barely 1 mm. long, pinched at 
the base, short -beaked. 

In sandy soil, Texas. Also in tropical America. Spring to fall. 

29. Cyperus Iria L. Annual, bright green. Leaves mostly overtopped by the 
scape ; blades 2-4 mm. wide, revolute, striate: scapes erect, sometimes tufted, 2-5 dm* 
tall, smooth : bracts of the involucre usually 5, the longer ones surpassing the umbel, 
curved : umbel of 5-9 rays of various lengths, compound : spikelets narrowly oblong, 5-10 
mm. long, yellowish or brownish, numerous, 12-26-flowered, rather lax : scales obovate or 
nearly orbicular, fully 1 mm. long, thin, mucronulate, deciduous at maturity: achenes 
sharply 3-angled, oblong-obovoid, about 1 mm. long, reddish, minutely apiculate, slightly 
surpassing the scales. 

In swamps mostly near the coast and rice fields, North Carolina to Florida and Texas. Naturalized 
from the tropics. Spring to fall. 

30. Cyperus distans L. Perennial, bright green. Leaves often overtopping the 
scape; blades 5-12 mm. wide, striate: scapes 3-15 dm. tall, erect, smooth, not jointed: 
bracts of the involucre 5, the longer ones surpassing the umbel, ascending, spreading : 
umbels compound, of several slender rays and one or more spikes sessile in tlie involucre : 
spikelets numerous, very slender, linear-filiform, 1-2.5 cm. long, chestnut-colored-, spicate 
and rather loosely disposed : scales oblong, fully 2 mm. long, blunt, sharply keeled : achenes 
3-angled, narrowly oblong-obovoid, 1.5 mm. long, abruptly pointed. 

In swampy grounds or wet woods, North Carolina and Georgia. Widely distributed in the tropics. 
Spring to fall. 

31 Cyperus cephaMnthus Torr. & Hook. Perennial, bright green. Leaves over- 
topped by the scape ; blades mostly 5-8 mm, wide, rough on the margins and the nerves 
beneath: scapes erect, 6-15 dm. tall, rough on the angles near the top : bracts of the in- 
volucre often 4 or 5, several much elongated and surpassing the umbel, drooping in age : 
umbel of 4-7 rays and one or more spikes sessile in the involucre : spikelets linear or oblong- 
linear, numerous and densely capitate, 6-10 mm. long, light chestnut-colored, scales oval- 
elliptic, 3 mm. long, acute, with several sharp ribs along the back, loosely imbricated, 
deciduous: achenes 3-angled, elliptic or obovoid-elliptic, barely 1.5 mm, long, rather ab- 
ruptly pointed. 

In low grounds, Louisiana and Texas. Spring- to fall. 

32, Cyperus Hispan L. Perennial by short rootstocks. Leaves reduced to mem- 
branous acuminate sheaths : scapes weak, tufted, 3-10 dm. high : bracts of the involucre 
about 2, usually less than 2 mm. wide : umbel simple or compound, the longer rays 2-5 
cm. long : spikelets few, capitate, linear, acute, many-flowered, 6-12 mm. long, about 1 
mm. wide : scales oblong or oblong-lanceolate, reddish brown, acute, mucronulate, keeled. 






CYPERACEAE 



169 



3-nerved : racliis winged: stigmas 3: achene 3-angledj broadly obovoidj 0.5-0,7 mm. 
long, obtuse, nearly white, much shorter tlian the scale. 

In swamps and sandy bogs, Virginia to Florida and Texas, mostly near the coast. Also in tropical 
America and in the ^varmer parts of Europe, Asia and Australia. Summer and fall. 

33. Cyperus dentatus Torr. Perennial by scaly rootstocks which sometimes bear 
small tubers. Leaves keeled; blades 2-4 mm. wide: scapes rather stiff, 2-5 dm. tall: 
bracts of the involucre 3-4, 1 or 2 usually exceeding the Inflorescence : umbel somewhat 
compound ; longer rays 2.5-7.5 cm. long : spikelets linear, very flat, many-flowered, mostly 
blunt, 10-20 mm. long, nearly 4 mm. wide: scales light reddish brown, ovate-lanceolate, 
thin, keeled, 5-7-nerved, mucronate, separating from the rachis Mdien mature, their tips 
spreading, causing the spikelet to appear toothed : stigmas 3, exserted : achene 3-angled, ob- 
ovoid, about 0.8 mm. long, obtuse, mucronate, light brown, much shorter than the scale. 
>Scales of the spikelets often modified into tufts of small leaf-like bracts. 

In sandy swamps and on river shores, Maine to northern New York, South Carolina and West Vir- 
Siuia. Summer and fall. 

34. Cyperus multiradiatus (Torr.) Mohr. Perennial, yellowish green. Leaves 
overtopped by the scape ; blades firm, 2-5 mm. broad, smooth : scai)es solitary, 2-4 dm. tall, 
smooth : bracts of the involucre 3-5, one or more of them surpassing tlie umbel, ascending : 
•umbel of 5-10 rays, all of different lengths : spikelets linear or linear-lanceolate, 1-2.5 cm. 
long, 3-4 mm. wide, yellow, 30-70-flowered, numerous : scales ovate, fully 2 mm. long, 
merely acute, scarious margined, minutely hooded at the apex, closely imbricated, faintly 
7-nerved, peslstent : achenes 3-angled, broadly ovoid, 0.8 mm. long, lustrous, brown. 
[(7. dentatus (3 f multiradiatus Torr, C. LeContei Torr.] 

In sand, Florida to Louisiana. Spring to fall. 

35. Cyperus rotiindus L. Perennial by scaly tuber-bearing rootstocks. Leaf-blades 
3-6 mm. wide : scapes rather stout, 1-5 dm. high, usually longer than the leaves : bracts 
of the involucre 3-5: umbel 3-8-rayed, the longer rays 5-11 cm. long: spikelets linear, 
•clustered; few in each cluster, acute, 8-20 mm. long, 2-3 mm. wide : scales dark purple- 
brown or with green margins and center, ovate, acute, appressed, about 3-nerved on the 
keel : stigmas 3, exserted : achene 3-angled, linear-oblong, about 1 mm. long, about ^ as long 
as the scale. 

In fields, Virginia to Florida. Kansas and Texas. Also in tropical America, and widely distrib- 
uted in the Old World. Summer and fall. 

36. Cyperus Hdllii Britton. Perennial by scaly rootstocks. Leaves with blades 
about 4-6 mm. wide : scapes rather stout, 6-9 dm. tall, about equalled by the leaves : in- 
volucral bracts 3-6, the longer much exceeding the inflorescence : umbel compound, its 
longer rays 7-10 cm. long, the raylets sometimes 2.5 cm. long : spikelets mmierous, loosely 
clustered, linear, 7-15-flowered, 10-10 mm. long, 2-3 mm. wide : involucels setaceous : 
scales ovate, acute, strongly 7-9-nerved, dark reddish brown or with llgliter margins, their 
tips not appressed: stigmas 3, much exserted: achene linear-oblong, 1.5 mm. long, 3- 
angled, about 2 as long as the scale. 

On plains and prairies, Kansas and the Indian Territory to Texas. Summer and fall. 

37. Cyperus escul6ntus L. Perennial by scaly tuber-bearing rootstocks. Leaves 
light green ; blades 4-8 mm. wide, the midvein prominent : scapes usually stout, 3-8 dm. 
tall, commonly shorter than the leaves : bracts of the involucre 3-6, the longer much ex- 
ceeding the inflorecence : umbel 4-10-rayed, often compound : spikelets numerous in loose 
spikes, straw-color or yellowish brown, flat, spreading, 1-2.5 cm. long, about 3 mm.^ wide, 
many-flowered : scales ovate-oblong, rather acute, 3-5-nerved : rachis narrowly winged : 
stigmas 3 : achene obovoid, fully 1 mm. long, obtuse, 3-angled. 

In moist fields, New Brunswick to Minnesota, Nebraska. Florida and Texas. Also on the Pacific 
coast from California to Alaska, in tropical America, and widely distributed in the Old World. Some- 
times a troublesome weed. Summer and fall.— A form with very slender spikelets about 2 mm. wide or 
narrower, is C. escukntm august ispicdtus Britton ; it ranges from Massachusetts and Missouri to South 
Carolina. Chufa. 

38. Cyperus articul^tus L. Perennial, pale green. Leaves reduced to a few 
scales at the base of the scape or sometimes with a few well developed blades : scapes erect, 
8-20 dm. tall, transversely septate, terete, smooth : bracts of the involucre mostly 3, ovate 
or linear-lanceolate, much shorter than the umbel, erect or nearly so: umbel of 4-10 
slender, curved rays, compound : spikelets slender, narrowly linear, 2-5 cm. long, or 
sometimes shorter,' deep straw-colored, not crowded, 30-50-flowered : scales elliptic or 
ovate, fully 3 mm. long, acutish or rather blunt, faintly ribbed, closely imbricated : achenes 
3-angled, oblong or cuneate-oblong, fully 1 mm. long, somewhat lustrous, pinched at the 
apex. 

In sandy swamps, South Carolina to Florida and Texas. Throughout the tropics. Spring to fall. 

39. Cyperus erythrorhizos Muhl. Annual. Leaf-blades 3-8 mm. wide, rough- 
margined : scapes tufted, stout or slender, 7-50 cm. tall : bracts of the involucre 3-7, some 



170 



CYPERACEAE 



of them 3-5 times as long as the inflorescence : umbel mostly compound : spikelets linear, 
rather acute, 6-25 mm. long, less than 2 mm. -wide, compressed, many-flowere<l, cro^vdod 
in oblong, nearly or quite sessile spikes : scales bright chestnut-brown, oblong-lanceolate, 
mucronulate, loose : stigmas 3 : achene sharply 3-angled, oblong, ab^ut 1 mm. long, pointed 
at both ends, pale, i ^s long as tlie scale. 

In wet soil, southern Ontario to Massachusetts, Nebraska, Kansas, Florida, Texas and California, 
Summer and fall. 

40. Cyperus digitatus Roxb. Annual, yellowish green. Leaves sometimes over- 
topping the scape ; blades 4-15 mm. wide, sometimes with rough margins and nerved be- 
neath : scapes commonly solitary, 3-12 dm. tall, 3-angled, smooth : bracts of the involucre 
6-10, the longer ones surpassing the umbel : umbel compound, of 5-8 more or less elon- 
gated rays, and one or more spikes sessile in the involucre : spikes about 1 cm. thick : 
spikelets laxly disposed, linear-subulate, 6-10 mm. long, chestnut-colored, 10-15-flo\vered, 
numerous : scales broadly oblong, about 2 mm. long, closely appressed, abruptly pointed 
or cuspidate, with pale hyaline margins: achenes 3-angled, fully 1 mm. long, elliptic or 
oblong, pale brown. [C. erythrorhizos var. ertctm Britton.] 

In low grounds or swamps, Texas and Mexico. Spring to fall. 

41. Cyperus H^lei Torr. Annual. Leaf-blades 6-8 mm. wide, very rough-mar- 

fined : scapes stout, 6-10 dm. tall, about equalled by the leaves : bracts of the involucre 
-8, much elongated : umbel compound, several-rayed : spikes cylindric, sessile or very 
nearly so, exceedingly dense, 1-2.5 cm. long: spikelets very numerous, linear, 3-5 mm. 
long, 1 mm. w^ide, spreading: scales brown, keeled, indistinctly 5-nerved, oblong, mucronu- 
late : stigmas 3 : achene 3-angled, about 1 mm. long. 

In swamps, south Missouri to Tennessee, Louisiana and Florida. Summer and fall. 

42. Cyperus Florid^nus Britton. Perennial, bright green. Leaves mostly reduced 

to a few basal scales and several filiform blades : scapes tufted, erect or reclining, 1-7 dm. 

long, filiform or wiry : bracts of the involucre 2, one about as long as the inflorescence, the 

other longer: umbel capitate, sessile: spikelets linear-subulate, 6-10 mm. long, crowded, 

chestnut brown : scales broadly oblong, fully 2 mm. long, blunt, closely imbricated, ribbed 

on the back, very firm : achenes 3-angled, oblong or nearly so, about 1.5 mm. long, dark 
brown, dull. 

In sand, southern Florida and the West Indies. Spring to fall. 

43. Cyperus Engelmdnnii Steud. Annual. Leaves elongated; blades 4-6 mm. 
wide, flaccid, roughish on the margins : scapes slender, 15-75 cm. tall : bracts of the in- 
volucre 4-6, the longer exceeding the umbel : umbel often compound, the spikelets often 
densely crowded, very commonly linear, subterete, 1-2.5 cm. long, 5-15-flowered : rachis 
narrowly winged : scales greenish brown, oTjlong, obtuse, thin, faintly 3-5-nerved on the 
back, distant, the successive ones on each side of the spikelet separated by a space of about 
J their length : stigmas 3 : achene linear-oblong, 3-angled, f as long as the scale, about 2 
mm. long. 

In wet soil, Massachusetts to southern Ontario, ■Wisconsin, New Jersev and Missouri. Summer 
and fall, 

44. Cyperus speciosus Vahl. Annual. Leaf-blades rough-margined, 3-5 mm. wide, 
the midvein prominent: scapes usually tufted, 10-40 cm. tall, reddish toward the base: 
bracts of the involucre much exceeding the umbel : umbel 3-7-rayed, the primary rays 
2-15 cm. long : involucels narrow : spikes dull brown : spikelets subterete, very narrowly 
linear, 8-25 mm. long, less than 2 mm. thick, 10-30-flowered, falling away from the axis 
at maturity : scales dull brown, thin, not tightly appressed, ovate, obtuse, faintly 3-5- 
nerved on the back : rachis-wings broad, clasping the achene, persistent : stigmas 3, 
slightly exserted : achene obovoid, barely 1.5 mm. long, pale, 3-angled, about \ as long as 
the scale. 

In marshes, eastern Massachusetts and Ehode Island to Ohio, Minnesota, Florida, Texas and Cali- 
fornia. Snmmer and fall.— A variety with reddish spreading or slightlv recurved scales, is C. speciosus 
ferruf/fniscens (Boeckl.) Britton ; its range is from Missouri to Texas and New Mexico. Another variety 
with about the same range, C. speciosus parvus (Boeckl.) Britton, has scapes 2-7 cm. high, a very simple 
umbel and generally a single cluster of short spikelets. 

45. Cyperus ftrax Vahl. Annual, closely related to the next preceding species, but 
with smooth-margined, shorter and broader leaf-blades : bracts of the involucre sometimes 
but little exceeding the inflorescence : umbel often compact, the rays mostly short : spikes 
yellowish or grayish brown : spikelets linear, subterete, 10-20-flowered, 16-25 mm. long, 
abouj 2 mm. thick : scales ovate-oblong, appressed, imbricated, obtuse, rather firm, green 
and 7-9-nerved on the back, yellowish on the sides : stigmas 3 : rachis broadly winged : 
achene 3-angled, narrowly obovoid, obtuse, about 1-1.5 mm. long. 

In wet soil, Missouri to California, and widely distributed in tropical America. Summer and fall. 



CYPEEACEAE 



171 



46. Cyperus Egg^rsii Boeckl. Annual, pale or bright green. Leaves commonly 
overtopping the scape, rough-margined : scapes 3-9 dm. tall, smooth : bracts of the 
involucre mostly 5, somewhat broader than the leaf-blades, much surpassing the umbel : 
umbel of 2-4 rays 1-3 cm. long, compound : spikes several to many : spikelets greenish 
brown, 4-7 mm. long, very brittle : scales blunt, less than 2 mm. long : achenes oblong, 
fully 1 mm. long, abruptly pointed at the apex, pinched at the base, straight, brown. 

In low grounds, southern Texas. Also in tropical America. Spring to fall. 

47. Cyperus oxycarioidea Britton. Annual, bright green. Leaves mostly over- 
topped by the scapes ; blades 3-8 nun. wide, roughish on the margins : scapes 5-12 dm. 
tall, 3-angled, smooth : bracts of the involucre usually 5, several much longer than the 
umbel, spreading : umbel capitate, the spikes congested into a dense terminal cluster : spike- 
lets linear-subulate, numerous, light green-brown, 6-10 mm. long, brittle, 8-12-flowered, 
densely crowded : scales oval-oblong, about 2 mm. long, blunt, delicately ribbed, closely 
imbricated : achenes 3-angled, oblong-obovoid, 1.5 mm, long, pale brown, slightly curved. 

" In ?andy swamps, southern Texas and Central America. Spring to fall. 

48. Cyperus Martindalel Britton. Perenial, bright green. Leaves overtopped by 
the scape ; blades filiform by the revolute margins, smooth : scapes tufted, erect, 2-7 dm. 
tall, 3-angled, smooth: bracts of the involucre 3-5, slender like the leaf-blades, several 
much elongated : umbel capitate, or with 1-3 slender rays : spikes globular, 1-2 cm. in 
diameter : spikelets linear or linear-subulate, G-10 ram. long, yellowish green, densely 
crowded|j. scales broadly oblong, 2-2,5 mm. long, prominently ribbed, often becoming 
eroded at the apes, spreading at maturity : achenes 3-angled, oblong, 2 mm. long or nearly 
so, brown, dull. 

In sand, Georgia to Florida and Louisiana, Spring to fall. 

49. Cyperus setigerus Torr. & Hook. Perennial, bright green. Leaves over- 
topped by the scape ; blades 4-10 mm. wide, rough at least' on the margins : scapes erect, 
6-12 dm. tall, smooth : bracts of the involucre 3-5, with scabrous margins, the longer ones 
much surpassing the umbels, spreading ; umbels of usually 6-9 slender smooth or scabrous 
rays, and one or more spikes sessile in the involucre: spikelets linear, 1-2.5 cm. long, 
chestnut-brown, rather numerous: scales lanceolate, 3-4 mm. long, acute, rather closely 
imbricated, ribbed on the back : achenes 3-angled, oblong-prismatic, 1.5 mm. long, pinched 
at the apex. 

In low grounds, Texas and New Mexico. Spring to fall. 

50. Cyperus strigosua L. Perennial by basal tuber-like corms. Leaves rough -mar- 
gined, 4-6 mm. wide : scapes rather stout, 3-9 dm. tall : the longer bracts of the involucre 
much exceeding the umbel : umbel several-rayed, some of the primary rays often 10-15 cm. 
long, their sheaths terminating in two bristles : involucels setaceous : heads oblong or ovoid : 
spikelets flat, linear, 8-19 mm, long, 2 mm. wide or less, 7-15-flowered : scales straw- 
colored, oblong-lanceolate, subacute, strongly several-nerved, appressed : stigmas 3 : achenes 
linear-oblong, 3-angled, about 2 mm. long, acute, about J as long as the scale. 

In moist meadows, swamps or along streams, Maine to Ontario, Minnesota, Nebraska, Florida and 
Texas. Summer and fall. — Several varieties have been described : C strif/osus robitstior Kunth, has a 
compound umbel and large spikelets 16-25 mm. long with 10-25 flowers ; it occurs with the type ; C\ 
strigosus capitdtus Boeckl., has the umbel simple or nearly simple, and the spikelets 8-14 mm. long, 
densely crowded in subglobose heads ; its range is like that of the type ; C strigosus compositu)^ Britton, 
has a compound umbel and spikelets 8-13 mm. long, with only 4 or 5 flowers ; it ranges from Xew York 
to Iowa and Alabama. C. strigosus gracilis Britton, is very slender, with leaves overtopped by the scape, 
umbel of 1-3 short rays, bearing few linear spreading spikelets ; it is confined to Arkansas and Texas ; 
and C strigosus elongdtus (Torr.) Britton, has much elongated rays bearing single capitate clusters, North 
Carolina and Texas. 

51. Cyperus stendlepis Torr. Perennial, bright green. Leaves overtopped by the 
scapes ; blades 8-16 mm. wide, very rough on the margins, pale beneath : scapes erect, 5-12 
dm. tall, smooth, 3-angled : bracts of the involucre 3-6, the longer ones much surpassing 
the umbel, spreading : umbel simple or compound, of 6-9 rays of various lengths ana one or 
more spikes sessile in the involucre: spikelets numerous, linear, 15-20 mm. long, bright 
straw-colored, 5-12-flowered : scales linear or linear-lanceolate, 4-5 mm. long, prominently 
ribbed and deciduous at maturity, loose and somewhat spreading: achenes 3-angled, ob- 
long-prismatic, about 2 mm. long, brown, abruptly pointed at the apex, pinched at the 
base. 

In swamps or low grounds, Xorth Carolina to Florida and Texas. Summer and fall. 

52. Cyperus refrdctus Engelm. I^Perennial by tuber-like corms. Leaf-blades 5-8 
mm. wide, rough-margined, elongated : scapes stout, smooth, 3-9 dm. tall : umbel 6-13- 
rayed, usually compound, the longer rays sometimes 20 cm. long, their sheaths terminating 
in 1 or 2 short teeth : involucels setaceous : raylets filiform : spikelets very narrowly linear, 
loosely spicate, acute, 1-2 cm. long, 1 mm. thick, 3-6-flowered, the upper spreading, the 
lower reflexed : scales yellowish green, oblong-lanceolate, obtuse, closely appressed, 9-11- 



172 



CYPERACEAE 



nerved, thin : stigmas 3, much exserted : achenes narrowly linear, about 3 mm. long, ob- 



tuse, apiculate, about 5 times as long as thick, and ^ as long as the scale. 

In dry fields or woods, New Jersey to North Carolina and Missouri. Summer and fall. 

• 53. Cyperus dissitiflorus Torr. Perennial, bright green. Leaves somewhat overtop- 
ping the scape, smooth or nearly so : scapes sometimes sparingly tufted, very slender? 
3-angled, smooth : bracts of the involucre mostly 4-6, the longer ones surpassing the 
umbel : umbel "of 3-5 slender rays and one or more spikes sessile in the involucre : 
spikelets linear-subulate, slender, 5-8 mm. long, spreading, 5-7-flowered, chestnut-colored, 
acute, not crowded, flattened: scales ovate to oblong, 2.5-3 mm. long, acute, closely im- 
bricated: achenes 3-angled, oblong-prismatic or slightly broadened upward, 1.5 mm. long, 
abruptly pointed. 

In sand, Florida to Texas. Spring to fall. 

54. Cyperus retrofractus (L. ) Torr. Perennial by tuber-like corras. Leaf -blades 
3-5 mm. wide : scapes usually rough-puberulent, at least above, mostly longer than the 
puberulent leaves : bracts of the involucre 4-7, the longer not greatly exceeding the umbel, 
sometimes shorter : umbel simple : rays 5-15 cm. long, their sheaths 2-toothed : heads 
oblong or obovoid : spikelets linear-subulate, 6-12 mm. long, about 1 mm. thick, 1-2- 
flowered, all soon strongly reflexed : flowering scales lanceolate, acute, the upper one 
subulate, all strongly several-nerved: stigmas 3 : achenes linear, 1.5-2 mm. long, 3- 
angled, obtuse, apiculate, f as long as the scale. 

In sandy soil, southern New Jersey to Florida, Kentucky, Arkansas and Texas. Summer and fall. 

55. Cyperus ovularis (Michx. ) Torr. Perennial by hard tuber-like corms. Leaves 
smooth ; blades 4-6 mm. wide : scape usually strict, smooth, 2-8 dm. tall, longer than the 
leaves : longer bracts of the involucre much exceeding the umbel : umbel simple, few-rayed; 
sheath of the rays truncate or slightly toothed : spikes globose, 8-14 mm. in diameter, very 
dense, the spikelets radiating in all directions : spikelets 4-7 mm. long, usually 3-flowered : 
scales ovate or ovate-lanceolate, obtuse or subacute, green, strongly several-nerved : stigmas 
3 : achenes linear-oblong, 3-angled, about 1.5 mm. long, 1-3 times as long as thick. 

In dry fields and on hills, southern New York to Florida, Illinois, Kansas and Texas.— C. ovularis 
spha^Hcus Boeclih J differs in its usually smaller heads, the spikelets more subulate, reddish brown. 
Arkansas to Texas. Summer and fall. 

56. Cyperus retrorsus Chapm. Perennial, pale green. Leaves overtopped by the 
scape ; blades 3-5 mm. wide, sometimes with rough margins and nerves beneath : scapes 
erect, 4-7 dm. tall, smooth : bracts of the involucre 7-10, mostly surpassing the umbel : 
umbel simple, of usually 8 slender rays : spikes narrowly obovoid, 1-1.5 cm. long : spike- 
lets densely crowded, subulate, 3 mm. long, the lower ones becoming reflexed : scales ob- 
long or nearly so, 2.5-3 mm. long, ribbed, closely appressed : achenes 3-angled, oblong- 
prismatic, nearly 2 mm. long, light brown. [C. retroversus Chapm.] 

On the sandy shore of Caximbas Bay, Florida. Spring to winter. 

57. Cyperus cylfndricus (Ell.) Britton. Perennial by hard corms. Leaf -blades 
2-3 mm. wide : scapes smooth, usually tufted, 1-5 dm. tall, longer than the leaves : longer 
bracts of the involucre much exceeding the umbel : umbel simple, the rays short, or the 
longer 2-7 cm. long, the sheaths 2-toothed : spikes very dense, cylindric, 5-15 mm. long, 
4-8 mm. in diameter, simple : spikelets 3-4 mm. long, flattish, 1-2-flowered, spreading or 
the lower reflexed : scales green, oblong : rachis winged : stigmas 3 : achenes linear-oblong 
about 1.5 mm, long, 3-angled, granular, apiculate, slightly more than ^ as long as the scale? 

In sandy soil and on the sea shore, southern New York to Florida and Texas. Summer and fall. 

58. Cyperus Pldnkii Britton. Similar to C. cyllndricus in habit, but stouter. Leaf- 
blades mostly 2.5-4 mm. wide, smooth : scapes solitary or sparingly tufted, 3-10 dm. tall, 
smooth, often surpassing the leaves : bracts of the involucre broader than the leaf-blades, 
sometimes 6-7 mm. broad, the longer ones surpassing the umbel : umbel simple, of 4-10 
rays, the larger 5-15 cm. long, mostly ascending: spikes very dense, cylindric, 15-20 mm. 
long, 10-15 mm. in diameter, green : spikelets 5-7 mm. long:, 3-4 flowered : scales ribbed : 
rachis winged : stigmas 3 : afhenes linear-oblong, 1.5 mm. long, 3-angled, coarsely granu- 
lar, apiculate. 

On plains and prairies, Oklahoma, the Indian Territory and Texas. Spring to fall. 

59. Cyperus cylindrostichys Boeckl. Perennial, pale green. Leaves overtopped 
by the scape ; blades 4-8 mm. wide, smooth : scapes often sparingly tufted, 3-15 dm. tall, 
3-angled, smooth : bracts of the involucre 5-8, the longer ones much surpassing the umbel : 
umbel simple or compound, of 6-12 slender rays and one or more spikes sessile in the in- 
volucre : spikes cylindric, 1.5-3.5 cm. long, mostly less than 1 cm. thick, usually com- 
pound : spikelets subulate, 4-5 mm. long, grayish brown or tinged with yellow, numerous. 



densely crowded, spreading or recurved : scales oblong or nearly so, 2.5-3 mm. long, blunt, 



CYPERACEAE 



173 



finely ribbed, closely imbricated : achenes S-angled, oblong-prismatic, nearly 2 mm. long, 
abruptly pointed. 

In sand, Florida to Texas. Spring to fall. 

60. Cyperus Lancastri^nsis Porter. Perennial by ovoid or oblong corms. Leaf- 
blades 4-6 mm. wide : scapes slender, smooth, mostly longer than the leaves, 3-8 dm. tall : 
bracts of the involucre 4-7, the longer much exceeding the inflorescence : umbel simple, 
5-9-rayed, the longer rays 5-10 cm. long, their sheaths nearly truncate : spikes oval, ob- 
tuse, 1-2.5 cm. long : spikelets densely clustered, 8-10 mm. long, linear, nearly terete, 
2-4-flowered, the lower reflexed, the middle ones spreading, all separating from the axis at 
maturity : scales green, strongly several-nerved, the flowering ones lanceolate, subacute : 
stigmas 3 : achenes linear, obtuse, 2.5-3 mm. long, apiculate, 2-3 times as long as thick, f 
as long as the scale. 

In dry fields, Xew Jersey and Pennsylvania to Virginia and Alabama. Summer and fall. 

61. Cyperus uniflorus Torr. & Hook. Perennial, bright green. Leaves overtopped 
by the scape; blades 2-4 mm. wide, smooth: scapes often tufted, slender, 1-7 dm. tall, 
smooth : bracts of the involucre 4-7, the longer ones surpassing the umbel : uuibel simple, 
of 3-6 slender rays and one or more spikes sessile in the involucre : spikes oval or ovoid, 
1.5-2 cm. long: spikelets spreading in all directions, usually curved, subulate, 8-12 mm. 
long, gray-green, attenuate, never densely crowded : scales various, narrow, loAver merely 
acute, upper more or less awn-tipped, closely imbricated : achenes 3-angled, oblong or 
slightly broadest above the middle, 2.5 mm. long, brown. 

In sandy swamps or low grounds, Arkansas and the Indian Territory to Texas, New Mexico and 
Mexico. Spring to fall. / 

62. Cyperus subuniflonia Britton. Similar to the next preceding species in habit, 
but more slender and smaller throughout. Umbels with fewer rays : spikes globular or 
ovoid-globose, 6-10 mm. long : spikelets more or less spreading, 3-5 mm. long, M'ithout 
conspicuous subulate tips, little if at all curved : achenes 3-angled, oblong, about 2 mm. 
long, abruptly pointed. 

In dry soil, the Indian Territory, Texas and Mexico. Spring to fall. 

63. Cyperus tetrdgonus Ell. Perennial, bright green. Leaves mostly overtopped 
by the scape ; blades 4-10 mm. broad, smooth or nearly so : scape often solitary, erect, 3-8 
dm. tall, smooth : bracts of the involucre 8-10, the longer ones surpassing the umbel, as- 
cending, spreading : umbel mostly compound, of 6-12 slender erect or ascending rays and 
one or more spikes sessile in the involucre : spikelets linear-oblong, plump, 4-6 mm, long 
acute, chestnut-colored, 4^6-flowered, spreading or the lower reflexed : scales oblong, fully 
3 mm. long, 9-11-nerved, closely imbricated : achenes oblong or elliptic, 3-angled, 2 mm. 
long, chestnut-colored, dull. 

In sandy soil, near the coast, North Carolina to Florida and Texas. Spring to fall. 

64. Cyperus flavus (Vahl) Nees. Perennial, bright green. Leaves overtopped by 
the scape ; blades 2-6 mm. wide, smooth : scapes often tufted, 1-6 dm. tall, smooth : bracts 
of the involucre mostly 4-6, the longer ones surpassing the umbel : umbel capitate, of 3-6 
sessile cylindric spikes, 1-2 cm. long, or occasionally with 2-3 short rays : spikelets 
densely crowded, 3-5 mm. long, spreading, chestnut-colored: scales ovate to oblong, 2-2.5 
mm. long, finely ribbed, often eroded at the apex, closely imbricated : achenes 3-angled, 
broadly elliptic to obovoid-elliptic, about 2 mm. long, brown, dull. 

In sand, Texas and tropical America. Spring to fall. 

65. Cyperus fuliginous Chapm. Perennial, deep green. Leaves overtopped by the 
scape ; sheaths blackish ; blades revolute, about as slender as the scape, smooth : scapes 
tufted, filiform, 1-4 dm. tall, smooth : bracts of the involucre 2, one much shorter than 
the other : spikelets crowded in a head about 1 cm. in diameter, linear-oblong, 4-7 mm. 
long, dark brown, 8-12-flowered, often apparently lateral : scales oval or ovate, barely 2 
mm. long, mucronulate, several-ribbed: achenes 3-angled, oblong-obovoid, barely 1.5 mm. 
long, dark brown, dull. 

In sand, Key West, Florida. Spring to winter. 

66. Cyperus filiculmis Vahl. Perennial by hard oblong corms. Leaf -blades 2-4 mm. 
wide, keeled : scape smooth, slender, or almost filiform, ascending or reclined, 1.5-4.5 dm. 
long, usually longer than the rough-margined leaves : spikelets densely clustered in 1-7 
globose heads, linear, acute, 5-11-flowered, subterete or compressed, 5-12 mm. long, 2 mm. 
wide or less : scales ovate, acute or obtuse, pale green, strongly 7-1 1 -nerved, appressed : 
stigmas 3 : achenes oblong or obovold, fully 2 mm. long, 3-angled, obtuse, apiculate, dull 
gray, f as long as the scale, about twice as long as thick. 

In dry fields and on hills, New Hampshire to Ontario, Minnesota, Nebraska, Florida, Kansas, 
Texas and northern Mexico. Spring and summer. 



»? 



174 



CYPERACEAE 



67. Cyperus Blodg^ttii Torr. Perennial, bright green. Leaves overtopped by the 
scapes ; blades 2-4 mm. Avide, smooth : scapes tufted, 1-3 dm. tall, 3-angled, smooth : bracts 
of the involucre 3 or sometimes 2 very small additional ones present, the longer ones sur- 
passing the umbel : umbel capitate or with one to three short rays : spikes 10-15 mm. in 
diameter: spikelets 20-40, oblong or linear-oblong, 6-8 mm. long, densely crowded, 1-10- 
flowered : scales oval to ovate, less than 2 mm. long, mostly 9-nerved, rather obtuse : 
achenes 3-angled, oblong, about 1 mm. long, brown, dull. 

In sand, Key West, Florida. Spring to winter. 

68. Cyperus ligularis L. Perennial, glaucous. Leaves sometimes overtopping the 
scape ; sheath colored at the base ; blades 6-20 mm. broad, serrulate, somewhat revolute : 
scapes erect, 5-12 dm. tall, 3-angled, smooth : bracts of the involucre 3-6, several much 
elongated : umbel compound, of 6-many short rays, often rather dense, or the rays rarely 
elongated : spikes cylmdric or oblong, 1-2 cm. long : spikelets 4-6 mm. long, gray to 
brown, densely crowded, spreading ; scales oval, 2.5-3 mm. long, blunt, closely imbricated 
delicately ribbed : achenes 3-angled, elliptic or slightly broadest above the middle, 1.5 mm. 
long, dark brown, dull. 

In sand or swamps, Florida. Also in the tropics of both hemispheres. Spring to winter. 

69. Cyperus Grayi Torr. Perennial by thick, hard oblong or ovoid corms. Leaves 
shorter than the scape, bright green ; blades 2 mm. wide or less : scapes tufted, ascending 
or reclined, stiff", smooth, very slender, 15-50 cm. long : bracts of the involucre 4-8 : 
umbel 4-10-rayed, simple, the longer rays 7-10 cm. long : sheaths of the rays truncate or 
nearly so : spikelets 5-10 mm. long, loosely capitate, compressed, linear, rigid, spreading : 
scales green, ovate, obtuse or subacute, strongly 13-15-nerved, rather widely spreading 
when old : joints of the rachis bi'oadly winged : stigmas 3 : achene oblong or oblong- 
obovoid, barely 2 mm. long, obtuse, apiculate. 

In sands of the sea shore and in pine lands, New Hampshire to Florida. Summer and fall. 

70. Cyperus echinatus (Ell. ) Wood. Perennial by tuber-like corms. Leaves pale 
green ; blades 3-4 mm. wide : scape slender, smooth, erect, mostly longer than the leaves : 
bracts of the involucre 5-10, the longer usually much exceeding the umbel : umbel 6-13- 
rayed : rays filiform, their sheaths short, mucronate ; spikelets 4-8 mm. long, linear, flat, 
capitate in globose heads : scales thin, pale green, appressed, ovate-lanceolate, acute, 9-13- 
nerved, with narrow scarious margins : joints of the rachis broadly winged : stigmas 3 : 
achene oblong-obovoid, 2 mm. long, about twice as long as thick. 

In dry or sandy soil, North Carolina to Missouri, Florida and Texas. Summer. 

71. Cyperus bnianeus Sw. Perennial, bright green. Leaves overtopped by the 
scape ; blades 2-7 mm. wide, smooth, sometimes involute : scapes erect, usually solitary, 
3-7 dm. tall, 3-angled, smooth : bracts of the involucre often 4-5, all of them or the longer 
ones surpassing the umbel, spreading : umbel compound, capitate, or 3-5 of the rays 
becoming 1-5 cm. long: spikelets linear or linear-lanceolate, 10-15 mm. long, chestnut- 
colored, densely crowded : scales oval or ovate-oval, nearly 3 mm. long, often apiculate, 
conspicuously ribbed : achenes 3-angled, elliptic-obovoid, fully 1,5 mm. long, dark-brown, 
granular. 

In sand, Florida. Also in tropical America. Spring to fall. 

72. Cyperus Ottonia Boeckl. Perennial, bright green. Leaves mostly overtopping 
the scape ; blades 4-12 mm. wide, with rough margins : scapes 3-12 dm. tall, 3-angled, 
smooth : bracts of the involucre usually 5 or 6, several conspicuously elongated : umbel 
compound, of 4-8 rays and 1 or more spikes sessile in the involucre : spikelets linear, 
1-1.5 cm. long, chestnut-colored, numerous, often crowded, 10-16-flowered: scales oblong 
or nearly so, fully 3 mm. long, acute, many-ribbed on the back, rather loosely imbricated : 
achenes 3-angled, oblong-obovoid, fully 1.5 mm. long, dark brown, dull. 

In wet sand, Florida and the West Indies. Spring to fall. 

5. KYLLINGA Eottb. 

Annual or perennial sedges, with slender triangular scapes bearing 2 or more bracts at 
the summit which form an involucre to the strictly sessile simple or compound, dense head 
of spikelets. Spikelets numerous, compressed, each with 1 perfect flower, falling away 
from the axis of the head at maturity, consisting of only 3 or 4 scales, the 1 or 2 lower 
ones small and empty, the middle one fertile, the upper empty or staminate. Scales 2- 

ranked, keeled. Perianth none. Stamens 1-3. Style deciduous from the summit of the 
achene. Stigmas 2-3. Achene lenticular or 3-angled. 

Upper scales of the spikelets with scabrous or ciliate keels. 

Involucre with all the bracts spreading: upper scales of the spikelet scabrous. 1. K.pumila, 

Involucre with one bract erect: upper scales of the spikelet serrulate-ciliate. 2. K, brevifolia. 

Upper scales of the spikelet with smooth keels. 3. K, odorata. 



CYPERACEAE 



175 



w 

1. Kyllinga pumila Michx. Annual. Leaves light green ; blades roughisb on the 
margins, usually less than 2 mm. wide : scapes densely tufted, filiform, erect or reclined, 
3-40 cm. long, mostly longer than the leaves : bracts of the involucre 3-5, elongated, 
spreading or reflexed : head oblong or ovoid-oblong, 6-7 mm. long, simple or commonly 
Avith 1 or 2 smaller ones at the base : spikelets about 3 mm. long, flat, 1-flowered, the 2 
empty lower scales more or less persistent on the rachis after the fall of the rest of the 
spikelet : scales ovate, acuminate or acute, thin, about 7-nerved : stigmas 2 : achene len- 
ticular, obtuse. 

In moist or wet soil, Virginia to Illinois, Missouri, Florida, Texas and Mexico. Summer and fall. 

2. Kyliinga brevifolia L. Perennial, pale green. Leaves mostly shorter than tlie 
scape ; blades 1-2.5 mm. wide, smooth : scapes very slender or filiform, 1-3 dm. tall, 
smooth : bracts of the involucre 3, one erect, the others spreading : spikes solitary, globose 
or ovoid, 5-10 mm. long, greenish, commonly inclined : spikelets oblong-ovoid, 2-3 mm. 
long, acuminate : scales various, the 2 outer minute, the third and fourtli ovate, w^ith re- 
curved tips and serrulate-ciliate keels : achenes lenticular, orbicular-obovoid, about 1 
mm. long. 

In low grounds or springy places, Georgia and Florida to Texas. Also in tropical America. 

Spring to fall, 

3. Kyllinga odorkta Valil. Annual or biennial, pale green. Leaves mostly shorter 
than the scape ; blades usually 2-4 mm. broad, smooth : scapes tufted, 1-3 dm. tall, 
smooth : bracts of the involucre 4-5, becoming reflexed : spikes whitish, 1-3, ovoid to 
cylindric, 8-15 mm. long : spikelets 3 mm. long, oblong-ovoid, 1-flowered or imperfectly 
2-flowered : scales various, the two lower ones barely i as long as the ovate smooth third 
and fourth scale, the fiftli enclosed in the fourth scale, larger than the first and second : 
achenes lenticular, obovoid, fully 1 mm. long. 

In wet soil and along roadsides, Georgia and Florida to Mississippi. Summer and fall. Through- 
cut tropical America. Spring to fall. 

6. ERIOPHORUM L. 

Bog herbs, perennial by rootstocks. Stems erect, triangular or nearly terete. Leaves 
with linear blades, or 1 or 2 of the upper ones reduced to bladeless sheaths, Spikelets ter- 
minal, solitary, capitate or in umbels, subtended by an involucre or 1-several bracts, or 
naked. Scales spirally imbricated, usually all fertile. Flowers perfect. Perianth of 6 or 
numerous filiform smooth soft bristles, which are white or brown, straight or crisped, and 
exserted much beyond the scales at maturity. Stamens 1-3. Style deciduous. Stigmas 3. 
Achene 3-angled, oblong, ellipsoid or obovoid. Cotton-gkass. 

Spikelets iimbellate : achenes obovoid, obtuse. 1. E. polystachyon . 

Spikelets capitate : achenes linear-oblong, acute. 2. E. Virginicum, 

1. Eriophortim polystachyon L. Stems stiflT, smooth, obtusely triangular above, 
4-9 dm. tall, all the sheaths blade-bearing : leaf-blades flat, 3-8 mm. wide, each tapering 
to a channeled rigid tip : bracts of the involucre 2-4, the longer ones commonly equalling 
or exceeding the inflorescence : spikelets 3-12, drooping, in a terminal umbel ; rays fili- 
form, smooth or rough : scales ovate-lanceolate, acute or acuminate, purple-green or 
brown : perianth bristles numerous, bright white, about 2.5 cm. long, 4-5 times as long as 
the scale : achene obovoid, obtuse, light brown. 

In bogs, Newfoundland to Alaska, to New Jersey, the mountains of Georgia, and Nebraska. Also 
m Europe and Asia. Summer. Hare's-tail. 

2. Briophorum Virginlcum L. Stems stiff, obtusely triangular above, smooth, 4-11 
dm. tall, rather leafy : leaf-blades narrowly linear, flat, 2-5 mm. wide, channeled toward 
the apex : bracts of the involucre 2-4, spreading or deflexed, 5-15 cm, long ; spikelets 
several or numerous in a dense terminal capitate cluster, erect or the outer spreading : 
scales ovate, acute, brown with a green center, about 5-nerved : perianth bristles numerous, 
dingy brown, about 3 times as long as the scale : achene linear-oblong, acute, apiculate, 
light brown. 

In bogs, Newfoundland to Manitoba, Florida and Nebraska. Summer and fall. 



FUIRENA 



Perennial herbs, with triangular stems and many-flowered terete spikelets in terminal 
and axillary clusters, or rarely solitary. Scales spirally imbricated, awned, the 1 or 2 
lower commonly empty. Flowers perfect. Perianth of 3 ovate, oblong or cordate-ovate, 
stalked, often awned seoals. nsuallv altprnatincr with as manv downwardly barbed bristles. 



176 



CYPERACEAE 



Stamens 3. Style not sM'ollenat the base, deciduous. StigmasS. Achene stalked or nearly 
sessile, sharply 3-angled, acute or niucronate, smooth. 

Leaves reduced to sheaths without blades, except sometimes near the top of the stem. 

Stems 2-6 dm. long : upper sheaths with barely any blades : achenes fully 1 mm. long. 

1. F, scu-poidea^ 
Stems 8-13 dm. long : upper sheaths with narrow blades : achenes barely 1 mm. long, 

2. F, longa. 
Leaves with well-developed blades. 

Awn at the apex of the sepal, or wanting. 3. F. squarrom. 

Awn arising from the back of the sepal below its apex. 4. F, sirnpkx, 

1. Fuirena scirpoidea Michx. Rootstocks elongated : stems widely tufted, slender, 
2-6 dm. tall, simple : leaves reduced to several sheaths 1-2 cm. long, with oblique mar- 
gins : bracts of the involucre 2-6 mm. long, appressed to the spike, acute or cuspidate : 
spikelets sessile, solitary or 2 or 3 together, oblong or ovoid-oblong, 5-12 mm. long, sessile: 
scales broadened upward, abruptly pointed, each with an erect awn, several-ribbed : sepals 
3 ; blades oblong to oval -oblong, about as long as the stalks : perianth bristles hispid, longer 
than the stalks of the sepals : achenes 3-angled, oval-rhombic, constricted at both ends, fully 
1 mm. long. 

In low sandy places, Georgia and Florida to Louisiana. Spring to fall. 

2. Fuirena Idnga Cliapm. Eootstocks slender : stems loosely tufted, very slender, 
8-15 dm. long, declining or reclining : leaves various, reduced to acute or acuminate sheaths 
2.5-3 cm. long on the lower part of the stem, near the top of the stem with very narro^r 
blades as long as the sheaths or slightly longer : bracts of the involucre 8-16 mm. long, 
acuminate : spikelets oblong-ovoid, 2-4 together, 10-15 mm. long : scales pubescent, with 
awns about as long as the obovate body : sepals with ovate or suborbicular blades : perianth 
bristles slightly hispid : achenes 3-angled, obovoid or oval, barely 1 mm. long. 

In low pine lands, w^estern Florida. Summer and fall. 

3. Ftiirena squarrosa Michx. Eootstock short, sometimes tuber-bearing : stems 
tufted, glabrous or nearly so, 5-50 cm. tall : leaf-blades flat, nearly or quite glabrous ; the 
lower sheaths sometimes pubescent: spikelets sessile, solitary or 2-10 together in capitate 
clusters, ovoid or ovoid-oblong, 6-12 mm. long, about 5 mm. in diameter: scales ovate or 
oblong, brown, pubescent, mostly obtuse, 3-nerved, each tipped with a stout, spreading or 
recurved awn nearly as long as the body : sepals 3 ; blades oblong, long-stalked, usually 
narrow^ed at both ends, the awn downwardly barbed or sometimes smooth : perianth-bris- 
tles mostly longer than the achene. 

In wet meadows and marshes, Massachusetts to Florida and Louisiana, mostlv near the coast. 
Also in Michi£?an and Nebraska Summer and fall.— A variety, F. squarrosa Mspida (Ell.) Chapm. with 
retrorsely barbed bristles reaching to the middle of the achene or its tip, rhomboidal or deltoid-ovate, 
truncate or cordate scales, each tapering into a short thick unbarbed awn or tip, ranges from New 
York to Florida and Texas. Another variety, F, squarrosa hrevistta Coville, with smooth perianth-bristles 
not exceeding the stipe of the achene; oval or suborbicular scales rounded at the apex and with a 
minute apiculation, ranges from North Carolina to Florida and Texas. 

4. Fuirena simplex Vahl. Similar to the preceding species in habit. Stems 1-5 dm- 
tall, glabrous : leaf-blades flat, glabrous or ciliate : scales numerous, each tipped with a 
spreading or reflexed awn : sepals 3 ; blades ovate-oblong, obtuse and usually notched at the 
apex, the awn smooth or downAvardly barbed : perianth-bristles retrorsely hispid, equalling 
or exceeding the sessile or short-stalked achene. 

In moist soil, Nebraska to Texas and Mexico. Summer and fall.— A form from the valley of the 
lower Rio Grande, Texas, larger throughout and with spikelets 2 cm. long is F. dmpkx macrostdchya 
(Britton) Coville. ^ ^ 

8. SCIRPUS L. 

Annual or perennial very small or very large caulescent or scapose herbs, the leaves 
sometimes reduced to basal sheaths. Spikelets terete or somewhat flattened, solitary, capi- 
tate, spicate or umbellate, subtended by an involucre of l-several bracts, or the involucre 
wanting in some species. Scales spirally imbricated, the 1-3 lower sometimes empty. 
FloAvers perfect. Perianth of 1-6 slender or rigid, barbed, pubescent or smooth bristles, 
or rarely none. Stamens 2-3. Style not swollen at the base, wholly deciduous from the 
achene, or its base persistent as a subulate tip. Stigmas 2-3. Achene triangular, lenticular 
or plano-convex. Bulrush. Ci.ub-rush. 

Involucre of a single bract, or wanting. 

Spikelets solitary, or rarely 2 in No. 5, terminal. 

Involucre wanting. 1. s. nanus. 

Involucre present, of a single bract. 

Perianth-bristles present: scales not keeled. 

Scapes terete : upper sheath with a subulate blade : perianth-bristles 
I 2. 5. caespitosus^ 



CYPEKACEAE 



177 



Scapes triangular; upper sheath with a linear blade: perianth-bristles 
upwardly barbed. 
Perianth-bristles wanting: scales keeled. 
Spikelets normally more than 1, usually several or numerous, often apparently 
lateral. 
Spikelets few, 1-12, appearing lateral. 

Scapes not sharply 3-angled : plants annual. 

Achene strongly transverse-rugose : perianth -bristles wanting. 
Achene smooth or very slightly roughened : perianth-bristles 4-6. 
Scapes sharply 3-angled : plants perennial by rootstocks. 

Spikelets acute : scales awned : involucral bract much surpassing the 

inflorescence. 
Spikelets obtuse: scales mucronate : involucral bract only slightly sur- 
passing the inflorescence. 
Spikelets several or numerous, in umbels or umbel-like clusters. 

Scapes sharply 3-angled : leaves with blades about as long as the scape. 
Scapes terete : leaves reduced to mere sheaths. 

Perianth-bristles downwardly barbed : achene gray, abruptly mucronate. 
Perianth-bristles short-plumose below : achene nearly white, nar- 
rowed above. 
Involucre of 2 or more bracts with flat blades. 
Spikelets not in dense globular heads. 

Spikelets few to several, capitate to umbellate, relatively large. 

Spikelets in simple clusters : achenes obovoid-oblong, pale brown. 
Spikelets in often compound clusters: achenes orbicular-obovoid, dark 
brown . 
Spikelets very numerous, in compound umbels or umbelled heads, relatively 
small. 

Perianth-bristles downwardly barbed, or wanting : spikelets in umbelled 
heads. 
Perianth-bristles present. 

Perianth-bristles equalling or slightly exceeding the achene : leaf- 
blades 6-16 mm. wide. 
Spikelets 3-8 in each head : scales obtuse : perianth-bristles barbed 

throughout. 
Spikelets 8-20 in each head: scales acute: perianth-bristles not 
barbed below. 
Perianth-bristles twice as long as the achene: leaf-blades 4-6 mm. 
wide. 
Perianth -bristles wanting. 
Perianth-bristles smooth or slightly pubescent : umbel mostly decompound. 
Perianth-bristles shorter than the scales or scarcely exceeding them. 
Perianth-bristles about as long as the achene : scales rather acute. 
Inflorescence merely terminal : spikelets 1 mm. thick : achenes 

not papillose. 
Inflorescence terminal and lateral : spikelets 2-3 mm. thick 
achenes papillose. 
Perianth-bristles much longer than the achene : scales mucronate. 
Perianth-bristles much exsertedi beyond the scales at maturity 
Spikelets sessile, in small heads. 
Spikelets, at least some of them, distinctly peduncled. 
Spikelets very numerous in one or several dense globular heads. 

Annual. Roots fibrous : 



3. S, ClintoiiiL 

4. S. carinatus. 



5. S. Hctllii, 

6. S. debilis. 



7. S. Americanus. 

8. S, Olneyi. 

9. S. cylindricus, 

10. S. lacustris, 

11. 5. Californicus, 



12. S. cawpestru, 

13. S. robustus. 



14. S. itjlvatiais, 

15. S. atrovirens. 

16. S. polyphyllus, 

17. S. GeoTfjiamis, 



18. 5. divaricatus, 

19. S./onttualis, 

20. 5. lineatus, 

21. S- cyperimts. 

22. 5. Eriophorum, 

23. S, CahtnsiB. 



1. Scirptis nlinuB Spreng. Annual. Roots fibrous : scapes filiform, flattened, 
grooved, tufted, erect or ascending, 2-5 cm. high, each bearing a scarious bladeless sheath 
near the base : spikelets solitary, terminal, ovoid-oblong, rather acute, 3-8-flowered, 2-3 
mm. long, not subtended by a bract : scales ovate or lanceolate, pale green, the lower ob- 
tuse, the upper subacute : perianth-bristles about 6, dowuAvardly barbed, longer than the 
achene : stigmas 3: achenes oblong, 1 mm. long, 3-angled, pale, pointed at each end. 



m 



^ In muddy places in salt marshes, Cape Breton Island to Florida and Texas and about salt springs 
New York and Michigan, Also on the Pacific coast of North America and oi 



Summer and fall. 



on the coasts of Europe. 



2. Scirpus caespitbsus L. Perennial. Scapes smooth, terete, densely tufted, light 
green, erect or ascending, almost filiform, wiry, 10-40 cm. long : basal sheaths numerous, 
membranous, imbricated, acuminate, the u])per one bearing a short very narrow blade : 
spikelet solitary, terminal, few-flowered, ovoid-oblong, about 4 mm. long, subtended by a 
subulate involucral bract of about its own length : scales yellowish brown, ovate, obtuse or 
subacute, deciduous: perianth-bristles 6, smooth, longer than the achene: stigmas 3: 
achenes oblong, 1.5 mm. long, 3-angled, smooth, brown, acute. 

^ ,. In bogs and on moist rocks, Greenland to Alaska, south to the mountains of New England, the 
Adirondacks, western New York, Illinois, Minnesota and British Columbia, in the Rooky Mountains to 
Colorado, and on the higher summits of the southern Alleghenies. Also in Europe and Asia. Summer. 

3, ScirpuB Clintonli A. Gray. Perennial. Scapes tufted, triangular, very slender, 
erect, 10-40 cm. tall, roughish on the angles : lower sheaths imbricated, one or more of 
them bearing short subulate blades, the upper one bearing a flat, narrowly linear blade 
shorter than the stem : spikelet solitary, terminal, ovoid, few-flowered, 3-4 mm. long, sub- 
tended by a subulate involucral bract: scales ovate, pale brown, acute: perianth-bristles 
3-6, filiform, upwardly barbed, as long as the achene or longer : stigmas 3 : a^chenes oblong, 
1.5 to nearly 2 mm. long, sharply 3-an^3ed, brown, smooth, obtuse. 

In drj' fields and thickets, New Brunswick to Michigan and North Carolina. Local. Summer. 

12 



178 



CYPERACEAE 



4. Scirpus carin^tus (H. &A, ) A. Gray. Annual, bright green. Scapes tufted, 
0.5-2 dm. tall, bristle-like, smooth : leaves solitary at the base of each scape, bristle-like : 
bracts of the involucre 1-3 cm. long, erect: spikelets solitary, ovoid, about 4 mm. long, 
apparently lateral, 6-8-flowered : scales ovate to reniform, acuminate, loosely imbricated, 
keeled, rather persistent : stigmas 3 : aclienes 3-angled, oval, 1.5 mm. long, brown, gran- 
ular. \_Isolepis carinata H. & A,] 

In low grounds, Tennessee to the Indian Territory, California, Alabama and Texas. Spring. 

5. ScirpuB Hdllii A. Gray. Annual. Scapes very slender, smooth, tufted, obtusely 
triangular, erect, striate, 1-3 dm. tall : lower sheaths oblique, and acuminate or mucronate, 
the upper one commonly bearing a filiform blade 1-6 cm. long : spikelets capitate in clusters 
of 1-7, oblong-cylindric, obtuse, many-flowered, 6-12 mm. long, about 2 mm. thick, ap- 
pearing lateral by the extension of the solitary involucral bract : scales ovate-lanceolate, 
light greenish brown, acuminate, keeled, cuspidate : perianth-bristles wanting : achenes 
obovoid-orbicular or slightly broader than high, black, plano-convex, mucronulate, trans- 
versely wrinkled, about 1 mm. in diameter. 

In wet soil. Massachusetts to Florida, Illinois, Colorado, Texas and Mexico. Summer and fall. 

6. Scirpus ddbilis Pursh, Annual, smooth : scapes slender, terete or nearly so, tufted, 
1.5-5 dm. high : sheaths obliquely truncate, the upper ones rarely bearing a short subulate 
blade : spikelets capitate, in clusters of 1-12, ovoid-oblong, subacute, many-flowered, ap- 
pearing lateral, the involucral bracts narrowly linear, 3-10 cm. long, erect or divergent : 
scales light yellowish brown with a green midvein, broadly ovate, obtuse, or acute : peri- 
anth-bristles 4-6, downwardly barbed, about as long as the achene : stigmas 2 or rarely 3 : 
achenes plano-convex, broadly obovoid or orbicular, 1,5-2 mm. long, smooth or slightly 
roughened, dark brown, shining, obtuse, mucronulate. 

In wet soil, Maine to Ontario, Minnesota, Georgia, Alabama and Nebraska. Summer. 

7. Scirpus Axnerlc^nuB Pers. Perennial by long rootstocks. Scapes sharply trian- 
gular, erect, stiff, 3-11 dm. tall : leaves 1-3 ; blades linear, keeled, shorter than the scape : 
spikelets oblong-ovoid, acute, 8-12 mm, long, capitate in clusters of 2-7, appearing as 
if lateral : involucral bract slender, 3-10 cm. long : scales broadly ovate, brown, often 
emarginate or sharply 2-cleft at the apex, the midvein extended into a subulate awn some- 
times 2 mm. long, the margins scarious : perianth-bristles 2-6, downwardly barbed, shorter 
than or equalling the achene : achenes obovoid, plano-convex, about 2.5 mm. long, smooth, 
dark-brown, mucronate. 

In fresh water and brackish swamps, nearly throughout North America. Summer.' 

8. Scirpus Olneyi A. Gray. Similar to the next preceding species. Scapes stout, 
ijharply 3-angled, with concave sides, 0.5-2 m. tall: leaves 1-3, 2-13 cm. long, or repre- 
:sented by mere sheaths: spikelets capitate in dense clusters of 5-12, oblong or ovoid-ob- 
long, obtuse, 5-8 mm. long, the involucral bract short, stout, erect, 1-3 cm. long : scales 
oval or orbicular, dark brown with a green midvein, emarginate or mucronulate, glabrous : 
perianth-bristles usually 6, slightly shorter than or equalling the achene, downwardly 
barbed: stigmas 2 : achenes obovoid, about 2.5 mm. long, plano-convex, brown, mucro- 
nate. 

In salt marshes, Massachusetts to Florida, Texas, Mexico and California, extending along the 
Pacific coast to Oregon. Also in Arkansas. Summer and fall. 

9. Scirpus cyllndricus (Torr.) Britton. Perennial by stout rootstocks. Scapes 
stout, 3-angled above, 1-2 m. high, the linear nodulose keeled dark green leaves nearly or 
quite as long : involucral bract 1-2.5 dm. long, erect: spikelets in an apparently lateral 
umbel, drooping, oblong-cylindric, acutish, 1-2 cm. long, primary rays of the umbel sub- 
tended by 1 or more subulate-linear bracts : scales ovate or ovate-lanceolate, pale-brown, 
acute, mucronulate: perianth-bristles 6, stout, rigid, about as long as the achene, serrate : 
stigmas 3 : achenes obovoid, 3 mm. long, excluding the beak, 3-angTed, light brown, smooth, 
abruptly subulate-pointed. 

In ponds and swamps, Maryland to Florida and Lousiana. Summer and fall. 

10. Scirpus lacilstris L. Perennial by rootstocks. Scapes stout, terete, smooth, 
erect, 1-3 m. tall, sometimes 2 cm. in diameter, sheathed below: involucral bract soli- 
tary, erect, shorter than the umbel : umbel compound, appearing lateral, its primary rays 
3-10 cm. long : bracts linear-lanceolate : spikelets becoming oblong-cylindric, in mostly 
capitate clusters of 2-5, sessile or some of them peduncled, 5-16 mm. long, 3-4 mm. in 
diameter : scales ovate or oblong, each with a strong midvein which is sometimes excur- 
rent : perianth-bristles 4-6, downwardly barbed, equalling or longer than the achene : 
stigmas 2 : achenes plano-convex, obovoid, 2-2.5 mm. long, gray, abruptly mucronate, dull. 

In ponds aiid swamps, nearly throughout North America. Also in the Old World. Summer and 
fall. Cat-tail Flag. 



CYPERACEAE 



179 



11. Scirpua Califdrnicua (C. A, Meyer) Britton, Perennial, similar to the next 
preceding species. Leaves reduced to basal sheaths : involucral bracts short, stoutly subu- 
late : umbel compound ; spikelets 6-10 mm. long, acute, peduncled or some of them sessile : 
scales brown, ovate, awn-pointed : perianth-bristles shorter than or equalling the achene, 
short-plumose below : stigmas 2 : achene obovoid, 2 mm. long, plano-convex, nearly white, 
narrowed above into a short tip, contracted at the base. 

In swamps, Florida to Louisiana, northern Mexico and California, and widely distributed in 
tropical America. Summer, 

12. Scirpus cainp6stris Britton. Perennial. Stems smooth, sharply triangular, 3-5 
dm. tall. Leaves usually pale green ; blades smooth, 2-4 ram. wide : bracts of the involucre 
2 or 3, the longer much exceeding the inflorescence : spikelets 3-10, in a dense terminal 
simple head, oblong-cylindric, 1.5-2.5 cm. long, 5-8 mm, thick : scales ovate, pale brown, 2- 
toothed at the apex, the midvein excurrent into an ascending or spreading awn : perianth- 
bristles 1-3, much shorter than the achene, or none : stigmas 2 : achenes lenticular, obovoid 
or oblong-ovoid, 3-3.5 mm. long, mucronulate, yellow-brown, their surface strongly cellu- 
lar-reticulated. 

On wet prairies and plains, Manitoba and Minnesota to the Indian Territory, Nevada and Mexico. 
Spring and summer. 

13. Scirpus robtistus Pursh. Perennial by rootstocks. Stem stout, stiff, 3-angled, 
with flat sides, smooth, 5-14 dm. tall : leaves dark green ; blades smooth, 5-10 mm. wide : 
involucral bracts 2-4, elongated, similar to the leaf-blades : spikelets ovoid-oblong, stout, 
1.5-2.5 cm, long, 8-10 mm. in diameter, 6-20 together in a dense terminal cluster: scales 
ovate, brown, puberulent, thin, the midvein excurrent into an, at length, reflexed awn 3-5 
mm. long : perianth-bristles 1-6, fragile, shorter than the achene, or none : stigmas 3 : 
achenes 3-3.5 mm. long, compressed, flat on the face, convex or with a low ridge on the 
back, obovoid-orbicular, dark brown. 

In salt marshes, Kova Scotia to Florida and Texas. Summer^and fall. 

L 

14. Scirpus sylvdticuB L. Perennial by long rootstocks. Stems triangular, stout, 
smooth, 1-2 m. tall, often overtopped by the upper leaves : leaf -blades 1-1.6 cm. wide, 
rough on the margins : bracts of the involucre 5-8, the larger often 3 dm. long or more : 
umbel terminal, very large, sometimes 2 dm. broad, about 3 times compound, the spikelets 
ovoid or ovoid-oblong, 3-5 mm. long, in capitate clusters at the ends oi the raylets : bract- 
lets of the involucels small, linear or lanceolate ; scales ovate-oblong, obtuse, brown with 
a green center : perianth-bristles 6, downw^ardly barbed, slightly exceeding the achene : 
stigmas 3 : achenes oblong, fully 1 mm. long, 3-angled, obtuse, nearly white, mucronulate. 

In swami)s, New Hampshire to North Carolina and Georgia. Also in Europe. Summer and fall. 

15. Scirpus atrdvirens Muhl. Perennial by rootstocks. Stems triangular, rather 
slender, leafy, 5-12 dm. high : leaf-blades elongated, nodulose, dark green, 6-12 mm. 
wide, one or two of them usually exceeding the inflorescence : spikelets ovoid-oblong, acute, 
densely capitate at the ends of the rays or raylets : involucels short : scales greenish brown, 
oblong, acute, the midvein excurrent : perianth-bristles nsuallv6, downwardly barbed above, 
naked below, about as long as the achene : stigmas 3 : achenes oblong-oDovoid, 1 mm. 
long, 3-angled, pale brown, dull. 

In swamps, Nova Scotia to Manitoba, Georgia and Louisiana. Summer. 

16. Scirpus polyphyllus Vahl. Perennial by rootstocks. Stems slender, sharply tri- 
angular, 3-11 dm. tall, very leafy : leaves 3-ranked ; blades 4-6 ram. wide, rough-margined : 
bracts of the involucre 3-6, the longer commonly somewhat exceeding the inflorescence : 
spikelets ovoid, about 3 mm. long, capitate at the ends of the raylets : scales ovate, bright 
brown, mostly obtuse, mucronulate : perianth-bristles 6, downwardly barbed above the 
middle, twice as long as the achene : stigmas 3 : achenes obovoid, fully 1 mm. long, 3- 
angled, with a broad face and narrower sides, short-pointed, dull. 

In Bwamps, wet woods and meadows, Massachusetts to Minnesota, Georgia, Alabama and Arkansas. 
Summer and fall. 

17. Scirpus Georgiknus Harper. Perennial by rootstocks. Stems terete or nearly 
so, 4-12 dm. tall : leaf-blades smooth, about 2 dm. long, and 1 cm. wide, or the upper ones 
smaller : bracts of the involucre mostly 3, the largest surpassing the inflorescence : umbel 
thrice compound : spikelets green, about 3 mm. long, 10-15-flowered, 5-10 in heads : scales 
orbicular-ovate, about 1.5 mm. long, the toothed awns spreading at the tips, the midrib 
green, with a whitish keel : perianth-bristles wanting : achenes broadly oblong, about 0.8 
ram. long, short-beaked. 

In alluvial soil, middle Georgia. Spring and summer. 

18. Scirpus divaricitus Ell. Stems obtusely triangular, rather slender, 6-11 dm. 
tall: leaf-blades 4-8 mm. wide, rouerh-marjrined : umbel decompound, the primary rays 



180 



CYPERACEAE 



very slender, sometimes 1.5 dm. long, spreading or drooping : spikelets mostly solitary at 
the ends of the raylets, 6-12 mm. long, 1 mm. thick : scales ovate, greenish brown : peri- 
anth-bristles 6, flexuous, shorter than the scales : stigmas 3 : achenes 3-angled, not papil- 
illose, nearly white, not shining. 

In swamps, Virginia and Kentucky to Missouri, Florida and Louisiana. Summer. 

19. Sciipus fontin^lis Harper. Related to S. divaricatus and S, lineatus; differing 
from both of these species by its curved stem and lateral umbels, from the former by its 
thicker spikelets and papillose achenes and from the latter by its merely acute scales and 
shorter perianth-bristles. 

On margins of pools, Leslie, Georgia. Summer. 

20. Sciipus lineatus Michx. Perennial by stout rootstocks. Stems triangular, 3-10 
dm. high : leaf-blades 4-8 mm. wide, flat, rough-margined : umbels decompound, the rays 
very slender, becoming pendulous : spikelets mostly solitary at the ends of the raylets, 6-10 
mm. long, about 2 mm. thick : scales ovate or oblong, reddish brown and each with a green 
midvein : perianth-bristles 6, weak, smooth, entangled, much longer than the achene : stig- 
mas 3 : achenes oblong or oblong-obovoid, 1 mm. long, pale brown, 3-angled, short-beaked. 

In swamps and wet meadows. New Hampshire to Ontario, Oregon, Georgia and Texas. Summer. 

21. Scirpus cyperinus (L. ) Kunth. Perennial. Stems smooth, stiff, 6-20 dm. tall : 
leaves elongated ; blades 3-6 mm. wide, rough-margined : bracts of the involucre 3-6, the 
longer much exceeding the inflorescence : umbel terminal, compound, the rays at length 
somewhat drooping : spikelets ovoid-oblong, 3-5 mm. long, in capitate clusters of 3-15 at 
the ends of the raylets : scales ovate or lanceolate : perianth-bristles 6, entangled, smooth, 
much longer than the achene, much exserted beyond the scales, and grayish brown at 
maturity : stigmas 3 : achenes 3-angled, barely 1 mm. long, beaked, nearly white. 

In swamps, Newfoundland to Ontario, Virginia and Tennessee. Summer and fall. 

22. Scirpus Eridphonun Michx. Similar to the next preceding species in habit. 
Involucre more ferruginous at the base : umbel with laxer branches, the rays elongated 
and drooping at the ends: spikelets ovoid or oblong-ovoid, 3.5-6 mm. mostly 4.5 mm. 
long, more deeply colored, at least some of them distinctly peduncled. 

In low grounds or swamps, New York to Arkansas, Florida and Texas. Summer and fall. 

23. Scirpus Cub^nsls Poepp. & Kunth. Perennial, glabrous. Scapes sometimes 
tufted, 2-7 dm. tall, sharply 3-angled : leaves basal ; blades 3-5 mm. wude : bracts of the 
involucre mostly 3-5, spreading : spikelets crowded into 1 or several very dense subglobose 
heads, about 12-flowered, 3-5 mm. long : scales .firm, 13-nerved, each with a short spread- 
ing tip, commonly ciliate along the keel : perianth-bristles wanting : stigmas 2 : achenes 
elliptic or slightly broadest below the middle, 2-2.5 mm. long, tapering into a slender beak. 

In swamps, Alabama and Louisiana. Also in the West Indies, eastern South America and Africa. 
Summer and fall. 



9. WEBSTERIA S. Hart Wright. 

Perennial caulescent aquatic herbs, with repeatedly branching stems. Leaves clustered, 
capillary. Umbel decompound. Bracts of the involucres similar to the leaves. Spikelets 
l-flowered, peduncled : scales 2 to each spikelet, the lower one sterile. Flowers perfect. 
Perianth of 6-10 commonly barbed nearly white bristles. Stamens 3. Style slender, de- 
ciduous above the base : stigmas 2. Achene lenticular, minutely pitted in lines. 

1. Webateria submSrsa (Sauv. ) Britton. Submersed, glabrous. Stems 3-12 dm. 
long, with internodes 8-25 cm. long, sheathed, the branches topped by decompound umbels : 
spikelets 8-12 mm. long : scales acuminate, the lower one 3-nerved within, empty, the 
upper 1-nerved, with reddish brown margins : perianth-bristles tortuous : achenes lenticu- 
lar, obovoid or oval, about 1.5 mm, long, each tipped with the base of the style. [SciVpu^f 
submerms Sauv. Websteria limnophila S- Hart Wright.] 

In lakes and ponds, peninsular Florida. Also in Cuba. Spring to winter. 



10. ELEOCHARIS K. Br. 

Annual or perennial scapose herbs. Leaves reduced to sheaths, or the lowest very 
rarely blade-bearing. Scapes simple, triangular, quadrangular, terete, flattened or grooved. 
Spikelets solitary, terminal, erect, several-many-flowered, not subtended by an involucre 
or rarely by 2 small bracts. Scales concave, spirally imbricated. Perianth of 1-12 bristles, 
usually retrorsely barbed, wanting in some species. Stamens 2-3. Stigmas 2 and achene 
lenticular or biconvex, or when 3, the achene 3-angled, but sometimes with very obtuse 



CYPERACEAE 



181 



1. E, interatincta, 

2. E, cellulosa. 

3. E, mutata. 



4. E. Rohbinsiu 

5. E. elangata. 



6. E. ochreata, 

7. E* praiicola. 

8. E. olivaeea. 

9. E, maculosa. 



10. E. capiUacea. 



11. £, atropurpurea, 

12. £". capitata, 

13. £. bicolor. 



4 

angles and appearing turgid. Base of the style presistent on the summit of the achene, 
forming a tubercle. Spike Rush. 

Spikeiet scarcely or not at all thicker than the scape : scales mostly leathery. 

Bristles 6, as long as the achene or shorter : scapes relatively stout. 

Scapes terete, at least above : achenes not cancellate. 

Achenes transversely ridged : scapes nodose-septate. 

Achenes copiously pitted : scapes continuous. 

Scapes sharply 4-angled : achenes cancellate. 

Bristles 7, longer than the achene : scapes relatively slender. 

Spikeiet 6-8-flowered : achenes about 2 mm. long, deeply pitted : scapes 3- 
angled. 

Spikeiet 12-20-fiowered : achenes about 1 mm. long, faintly pitted : scapes 
terete. 
Spikeiet manifestly thicker than the scape : scales mostly membranous. 
Style-branches or stigmas 2 : achene lenticular or biconvex. 

Upper sheath scarious, hyaline : plants perennial by slender rootstocks. 
Achenes about 0.5 mm. long. 

Scales pale green or rarely white: perianth-bristles longer than the 

achene. 
Scales brown : perianth-bristles shorter than the achene. 
Achenes about 1 mm. long. 

Scapes 2-10 cm. long: perianth-bristles longer than the achene. 
Scapes 10-35 cm. long : perianth-bristles as long as the achene. 
Upper sheath truncate, oblique or toothed, not scarious. 
Annuals with iibrous roots. 

Scapes capillary ; spikelets with 1-4 achenes. 
Scapes slender : spikelets with several to many achenes. 
Achenes black. 

Perianth -bristles 2-4, pale : achenes 0.5 mm. long : scapes 2-9 cm. 
tall. 

Perianth-bristles 5-8, brown : achenes 1 mm. long : scapes 5-25 
cm. tall. 
Achenes pale brown to white. 
Scapes filiform : achene white. 
Scapes slender : achenes pale brown. 
Scales of the spikelets obtuse. 

Perianth-bristles longer than the achene : spikelets ovoid. 
Perianth-bristles not longer than the achene, often short or 
wanting : spikelets cylindric. 
Scales of the spikelets acute. 
Perennials with horizontal rootstocks. 
Scapes nodose-septate. 
Scapes continuous. 

Scales pale green or straw-colored : scape relatively stout. 
Scales brown or dark green : scapes slender or filiform. 

Achenes 1.5 mm. long : tubercle conic. 
Achenes 1 mm. long or less : tubercle depressed. 
Style-branches or stigmas 3 : achene 3-angled|or turgid. 
Achene cancellate. 

Achene longitudinally ribbed. 
Achene not longitudinally ribbed. 

Scapes filiform : spikelets with 1-4 achenes. 
Scapes slender : spikelets with many achenes. 
Spikelets linear-oblong, often proliferous. 
Spikelets ovoid to conic-ovoid, not proliferous. 
Tubercle conic, smaller than the achene. 
Tubercle cap-like, as large as the achene or larger. 
Achene smooth, papillose, or irregularly ridged-reticulated. 
Scapes capillary or filiform. 

Spikelets terete or nearly so, 6-2- flowered. 
Spikelets oblong, 3-6 mm. long. 
Spikelets ovoid, 2-3 mm. long. 
Spikelets flattened. 2-6-flowered, often proliferous. 
Achene obovoid : tubercle deltoid or depressed. 

Achene oblong : tubercle abruptly subulate-tipped. 
Scapes slender or stout. 

Tubercle plainly distinguishable from the achene. 

Spikelets ovoid to oblong : achene not constricted at the neck. 
Achenes smooth. 

Tubercle flat, covering the top of the black achene. 
Tubercle ovoid-conic, acute, contracted at the base. 
Achenes papillose or irregularly ridged-reticulated. 
Achenes with the 3 angles ribbed, 

Achenes obtusely 3-angled. 

Scapes slender to nearly filiform : scales obtuse. * 

Bristles 2-4, shorter than the achene : achene strongly 

papillose to reticulated. 
Bristles 6, the longer as long as the achene : achene 

faintly reticulated. 
Scapes flattened : scales acute. 
Spikelets linear-cylindric : achene constricted at the neck. 
Tubercle long-conic, scarcely distinguishable from the achene. 



14. E, obtusa. 

15. E. Engelmannit 

16. E. lanceolata. 

17. E. nodidosn. 

18. E, macTOdachya, 

19. E, glauccscens . 

20. E. Ravenelii. 



21. E, acicularis. 

22. E. Chadaria, 

23. E. vivipara. 

24. E. tortilla. 

25. E, tuberculosa. 



26. E. Torreyana. 

27. E. microcarpa. 

28. E, prolifera. 
29- E. Baldwinii, 



30. E. melanocarpa, 

31. E. albida. 

32. E, tricostata. 



33. E, tenuU, 

34. E. arenicola. 

35. E, acuminata. 

36. E. cylindrical 

37. E. ToatdlcUa, 



1. Eleocharis interstfncta (Vahl) R. & S. Perennial by stout rootstocks. Scapes 
terete, hollow, nodose-septate, 4-9 dm. tall, the sterile ones sharp-pointed : sheaths mem- 



182 



CYPERACEAE 



branous, the lower sometimes bearing short blades :spikelet terete, cylindric, many-flowered, 
rather acute, 2.5-4 cm. long, 4 mm. in diameter, not thicker than the scape : scales ovate, 
orbicular or obovate, obtuse or the upper ones acute, narrowly scarious- margined, faintly 
many-nerved, persistent : perianth-bristles 6, rigid, retrorsely barbed, as long as the body of 
the achene, or shorter : stigmas 3, exserted : achenes obovoid, 1.5 mm. long, brown, shining, 
with minute transverse ridges, convex on one side, very obtusely angled on the other, 2 or 
3 times as long as the conic acute black broad-based tubercle. [E. equisetouks (Ell. ) Torr.] 

In water, Massachusetts to Michigan, Florida and Mexico. Also in the West Indies. Summer and 
fall. 

2. Eleocharls celluldsa Torr. Perennial by horizontal rootstocks. Scapes obscurely 
3-angIed and invested by discolored sheaths at the base, terete above, 3-7 dm. tall, con- 
tinuous : spikelet cylindric, 1.5-3 cm. long, 3-5 mm. thick : scales broadly obovate, with 
white hyaline margins^ appressed, rounded at the apex, minutely nerved : perianth-bristles 
6, slightly unequal, nearly smooth : stigmas 3 : achenes broadly obovoid, copiously pitted, 
1.5-2 mm. long excluding the tubercle, about as long as the bristles ; tubercle finally del- 
toid, about J as broad as the widest part of the achene. 

In marshes near the coast, Florida to Texas. Also in the West Indies. Summer and fall. 

3. Bleocharis mut^ta (L. ) R. & S. Perennial by stout rootstocks. Scapes sharply 
4-anffIed, stout, not nodose, 6-12 dm. tall : sheaths purplish brown or green, sometimes 
bearing short blades : spikelet terete, cylindric, 2-5 cm. long, 4 mm. in diameter, many- 
flowered, about as thick as the scape : scales broadly ovate or obovate, obtuse or the upper 
rather acute, scarious-margined, faintly many-nerved, persistent : perianth-bristles about 6, 
rigid, retrorgely barbed, about as long as the achenes : stigmas 3 : achenes obovoid, 2.5 mm. 
long, biconvex or slightly angled on the back, minutely cancellate, about twice as long as 
the conic acute tubercle which is truncate or contracted at the base. 

In ponds, streams and swamps, southern Ontario to New Jersey, Michigan, Alabama, Missouri, 
Texas and Guatemala. Also in the West Indies and South America. Summer and fall. 

4. Eleocharis Robbinsii Oakes. Perennial by slender rootstocks. Scapes slender, 
3-angled, 1-6 dm. long, sometimes producing numerous filiform flaccid, sterile branches 
from the base : sheaths appressed, obliquely-truncate ; spikelet subulate, few-flowered, not 
thicker than the scape, 1-2 cm. long, 2 mm. in diameter : scales lanceolate or oblong- 
lanceolate, strongly concave, faintly several-nerved, persistently clasping the rachis, nar- 
rowly scarious-margined : stigmas 3 : perianth-bristles 7, equalling the achene and tubercle, 
retrorsely barbed : achenes obovoid, 2 mm. long, light brown, deeply pitted, biconvex or 
obtusely angled on the back, twice as long as the conic-subulate flattened tubercle, which 
has a raised ring around the base. 

In shallow water, New Brunswick to Michigan and Florida. Summer and fall. 

5. Eleocharis elongkta Chapm. Perennial from very slender rootstocks. Scapes 
slender, tufted, chiefly submerged, 3-10 dm. long, terete, accompanied by phyllode-like 
filiform sterile ones, tender: spikelet cylindric, 1-2 cm. long, 2-2.5 mm. thick, 12-20- 
flowered, acute : scales relatively distant, oblong-ovate, obtuse, prominently ribbed, with 
a green back and brown margins : perianth-bristles 7, plumose : achenes obovoid, faintly 
pitted, biconvex or slightly 3-angled, about 1 mm. long ; tubercle minute. 

In still water, Florida and Texas. Summer. 

6. Eleocharia ochre^ta (Nees) Steud. Perennial by slender rootstocks. Scapes 
very slender, or filiform, pale-green, 3-angled, 0.5-2,5 dm. tall : upper sheath with a white, 
hyaline, scarious limb : spikelet subacute, 2-3 times as thick as the scape, about 4 mm. 
long, 2-3 mm. in diameter, several-flowered : scales pale green, oblong-lanceolate, obtuse 
or the upper acute, hyaline, each with a faint midvein : perianth-bristles about 6, slender, 
retrorsely barbed, somewhat longer than the achene : stigmas 2 : achenes 0.7-1 mm. long, 
lenticular, obovoid, smooth, brown, 2-4 times as long as the conic acute tubercle. 

In wet soil, Virginia to Florida and Mississippi, Also in tropical America. Summer and fall. 

7. Eleocharis praticola Britton. Annual, relatively small. Scapes slender, 
tufted, 6 cm. tall or less : spikelet ovoid or oblong-ovoid, about 2 mm. long : scales 
brown, lanceolate or oblong-lanceolate, lax in age : perianth-bristles 5-7, retrorsely barbed, 
shorter than the achene: stigmas 2: achenes obovoid, about 0.5 mm. long, dark brown, 
shining, the tubercle very small. 

In low places, Osceola County, Florida. Spring. 

8. Eleocharls olivcicea Torr. Perennial by running rootstocks, often tufted and 
matted. Scapes very slender, bright green, erect or reclining, flattened, 2-10 cm, long : 
upper sheath with a white hyaline limb : spikelet ovoid, much thicker than the scape, 
several-many-flowered, about 4 mm. long, 2 mm. in diameter : scales ovate, acute, reddish 
brown, each with a green midvein and narrow scarious margins : perianth-bristles 6-8, 



CYPERACEAE 



183 



slender, retrorselj barbed, longer than the achene and tubercle : stigmas 2 : achenes obovoid, 
like those of £*. ochreata^ but twice as large, 3-4 times the length of the conic acute tubercle. 
In wet soil, Maine to southern Ontario, Pennsylvania, and South Carolina. Summer and fall. 

9. Eleocharis maculosa (Vahl) R. Br. Perennial by slender rootstocks. Scapes 
tufted, 1-3.5 dm. long, slender : spikelet ovoid, 5-12 mm. long, rather blunt, dense, purple- 
brown : scales ovate or oblong-ovate, scarious-raargined, rather persistent : perianth-bristles 
7-8, retrorsely scabrous, brown or rusty, as long as the achene : stigmas 2 : achenes obovoid, 
about 1 mm. long, chestnut-brown, shining, the tubercle abruptly pointed, pale. 

In wet ground, Texas. Also in Central and South America. Spring to fall. 

10. Eleocharis caplU^cea Kunth. Annual, diminutive. Scapes tufted, capillary, 
2-5 cm. long, sligntly 4-angled : spikelet linear-cylindric, 2-3 mm. long, with 1-4 achenes, 
deep brown or reddish : scales few, nearly oblong or oblong-lanceolate, the 2 lower mostly 
including the spikelet : perianth-bristles 4-6, about as long as the achene, retrorsely sca- 
brous : stigmas 2 : achenes lenticular, about 0.5 mm. long, exclusive of the slender conic 

tubercle, brown. 

About pine-land ponds and in wet sand, North Carolina to Florida. Also in Central and South 
America. Spring to fall. 

11. Eleocharis atropurpurea (Retz) Ivunth. Annual with fibrous roots. Scapes 
tufted, very slender, 2-9 cm. high : upper sheath 1-toothed : spikelet ovoid, many-flowered, 
subacute, 3-4 mm. long, 2 mm. in diameter, or less : scales minute, ovate-oblong, persist- 
ent, purple-brown except the midvein and very narrow scarious margins : perianth-bristles 
2-4, fragile, pale, minutely downwardly hispid, about as long as the achene : stigmas 2 : 
achenes jet black, shining, 0.5 mm. long, smooth, lenticular ; tubercle conic, minute, de- 
pressed but rather acute, constricted at the base. 

In moist soil. Iowa. Nebraska and eastern Colorado to Central America, east to Florida ; widely 
distributed in tropical America. Summer and fall, 

12. Eleocharis capit^ta (L. ) R. Br. Annual with fibrous roots. Scapes densely 
tufted, nearly terete, almost filiform, 0.5-2.5 dm. tall: upper sheath 1-toothed: spikelet 
ovoid, obtuse, much thicker than the scape, 3-5 mm. long, 2-3 mm. thick, many-flowered: 
scales broadly ovate, obtuse, firm, brown except the greenish midvein, narrowly scarious- 
margined, persistent : perianth-bristles 5-8, slender, downwardly hispid, as long as the 
achene : stigmas 2 : achenes obovoid, jet black, smooth, shining, 1 mm. long ; tubercle de- 
pressed, apiculate, constricted at the base, very much shorter than the achene. 

In moist soil, Maryland to Indiana, Florida and Texas. Also in the tropics. Summer and fall. 

13. Eleocharis bicolor Chapm. Annual, pale green. Scapes tufted, filiform, 0.3-2 
dm. long, sometimes procumbent, 4-angled : spikelet ovoid, 2-3 mm. long, rather blunt, 
8-12-flowered : scales ovate, obtuse, thin, loosely imbricated, with whitish margins and 
keel : perianth-bristles 3, fugacious : achenes lenticular, obovoid, 0.5 mm. long, papillose, 
about twice as long as the bristles ; tubercle broadly conic, about J as long as the body of 
the achene. 

In sandy soil, near the coast, Florida. Summer. 

14. Eleocharis obtusa Schult. Annual with fibrous roots. Scapes tufted, relatively 
stout, rather deep green, nearly terete, mostly erect, 0.5-5 dm. tall : upper sheath 1- 
toothed : spikelet ovoid or oblong-ovoid, obtuse, many-flowered, 3-13 mm. long, 3-5 mm. 
in diameter: scales thin, obovate, oblong-obovate or oblong-orbicular, obtuse, brown, each 
with a broad green midvein and scarious margins : perianth-bristles 6-8, deciduous, usually 
longer than the achene : stigmas 2 : achenes pale brown, shining, lenticular, obovoid-(»b- 
long, smooth, 1 mm. long or more; tubercle deltoid, acute, compressed, scarcely con- 
stricted at the base, about } as long as the achene. 

In wet Poil, New Brunswick to Ontario, British Columbia, Florida, Texas and Oregon.— A form 
with more slender generally decumbent or spreading scapes, smaller fewer-flowered spikelets with 
more spreading scales and a smaller achene, is E, obtusa jejuna Fernald. Summer and fall. 

15. Eleocharis Engelmdnnii Steud. Annual, quite similar to the next preceding 
species, but scapes commonly taller, sometimes 5 dm. high. Upper sheath obliquely truncate 
or 1-toothed : spikelet cylindric, obtuse or rather acute^ 4-16 mm. long, 2-3 mm. in diameter, 
many-flowered : scales pale brown with a green midvein and narrow scarious margins, ovate, 
obtuse, deciduous : perianth-bristles about 6, not longer than the achene or very short or 
wanting : stigmas 2 : achenes obovoid or cuneate-obovoid, fully 1 mm, long, brown, smooth, 
lenticular ; tubercle broad, low, covering the top of the achene, less than \ its length. 

In wet soil, Massachusetts to Virginia. Indiana, Arkansas, Texas and California.— The form with- 
out perianth-bristles, or mere rudiments, and generally stouter scapes, is E. Engelinannu dctonsa A. Gray. 
Summer and fall. 

16. Eleocharis lanceol^ta Fernald. Annual, bright green. Scapes tufted, slender 
or nearly filiform, 1-2.5 dm. tall : spikelet lanceolate in outline, 5-9 cm. long, about 2 or 
3 mm. thick, rather acute : scales pale, hyaline except green ribs, acute, rather appressed : 



184 



CYPERACEAE 



perianth-bristles overtopping the body of the achene : achenes broadly obovoid, fully 1 mm. 
long ; tubercle about ^ us high as the body of the achene. 
In moist soil, Arkansas to Texas, Summer and fall. 

17. Eleocharis nodulosa ( Roth) Schult. Perennial by horizontal rootstocks. Scapes 
closely tufted, relatively stout, 3-10 dm. tall, copiously nodose-septate, invested at the base 
by more or less discolored sheaths, constricted below the summit : spikelet conic-cylindric, 
acute, 1-2 cm. long, 4-6 mm. thick : scales closely imbricated, oblong-lanceolate, often con- 
stricted below the apex, 3-4 mm. long, scarious-margined : perianth-bristles very variable 
in length : aclienes obovoid, pinched at the base, about 1 mm. long, plump ; tubercle 
deltoid, about J the width of the body of the achene. 

In swamps, Florida to Louisiana and Arizona. Also in tropical America. Spring to fall. 

18. Eleocharis macrcst^chya Britton. Perennial by relatively short rootstocks, 
pale green or straw-colored. Scapes tufted, 2.5-12 dm. long, stout: spikelet narrowly 
cylindric or linear-lanceolate in outline, 1-2.5 cm. long, many-flowered, acute: scales ob- 
long-ovate to lanceolate, often rather acute, pale green or straw-colored with darker ribs : 
perianth-bristles 5-6, as long as the achene or somewhat shorter, retrorsely barbed, or 
sometimes very short: stigmas 2: achenes lenticular, obovoid, about 1.5 mm. long, ex- 
cluding the small cap-like tubercle, lemon-yellow. 

In low grounds, Arkansas to Nevada, Louisiana, Texas and Arizona, Spring to fall. 

19. Eleocharis glaucSscens (Willd. ) Schult. Perennial by horizontal rootstocks. 
Scapes tufted, slender, 1-9 dm. long, bright or deep green : spikelet oblong or oblong-lan- 
ceolate, 0.5-1.5 cm. long, acute or rather obtuse: scales brown or dark green, blunt or 
acute in age ; perianth-bristles usually 4, about as long as the achene or shorter or nearly 
wanting: stigmas 2 : achenes lenticular, obovoid, about 1.5 mm. long, excluding the nar- 
row conic tubercle, brown. 

In swamps or meadows, Ontario to Minnesota, Nebraska, Florida and Texas. Spring to fall. 

20. Eleochaiis Raven^lii Britton. Perennial, bright green. Scapes tufted, 3-5 
dm. long, slender: spikelet lanceolate or oblong-lanceolate in outline, 8-11 mm. long, 
acute : scales oblong to oblong-lanceolate, rather blunt, scarious-margined, brown on either 
side of the prominent midrib : perianth-bristles 4-5, somewhat shorter than the achene : 
stigmns 2 : achenes biconvex, plump, 1 mm. long or less, narrowly obovoid, somewhat con- 
stricted at the top, smooth or nearly so ; tubercle depressed. 

In sandy soil, southern Texas. Spring. 

21. Eleocharis aciculiiis (L. ) R. & S. Perennial by filiform stolons or rootstocks. 
Scapes tufted, finely filiform or setaceous, obscurely 4-jmgled and grooved, weak, erect or 
reclining, 5-20 cm. long : sheaths truncate : spikelet compressed, narrowly ovate or linear- 
oblong, acute, broader than the scape, 3-10-flowered, 3-10 mm, long, 1 mm. wide : scales 
oblong, obtuse, or the upper subacute, thin, pale green, usually with a narroAv brown band 
on each side of the midvein, deciduous, many of them commonly sterile : perianth-bristles 
3-4, fragile, fugacious, shorter thnn the achene: stigmas 3: achenes obovoid -oblong, 0.5 
mm. long, pale, obscurely 3-angled with a rib on each angle and 6-9 lower intermediate 
ribs connected by fine ridges ; tubercle conic, acute, } as long as the achene. 



In wet soil, throughout North America, except the extreme north. Also in Europe and Asia. 
Summer and fall.— A variety, E. acicularU radicavs (Poir,) Britton, is distinguished by its relatively 
stout scapes and thicker spikelets. Texas, California and Central America. 

22. Eleochaiis Chaetdria R. & S. Perennial or annual. Scapes tufted, 2-20 cm. 
long, curved, filiform or wire-like, smooth, barely constricted at the summit, with a green 
sheath at the base : spikelet erect, oblong or ovoid-oblong, 2-3 mm. long, 1-4-flowered, 
flattened : scales in 2 or 3 rows, thin, barely discolored : perianth -bristles 6, about as long 
as the achene, sometimes much reduced : stigmas 3 : achenes 3-angledj obovoid, barely 1 
mm. long ; tubercle pyramidal, shorter than the body of the achene. 

In sandy soil or low grounds, southern Alabama. Also in the West Indies and most tropical and 
warm-temperate regions. Spring to fall, 

23. Eleocharis vivipara Kunth. Perennial by horizontal rootstocks, pale green. 
Scapes very numerous, tufted, very slender, 1-3 dm. long, not rigid, sometimes spreading, 
barely constricted at the summit : spikelet linear-oblong, 4-7 mm. long, acutish, often 
sparingly proliferous : scales oblong or ovate-oblong, blunt, scarious-margined, closely im- 
bricated, somewhat discolored : perianth-bristles 6, barbed, unequal in length : achenes ob- 
ovoid, nearly white, 3-angled, plump, about 1 mm. long, finely cancellate ; tubercle deltoid, 
or depressed, shorter than the body of the achene. 

In low grounds and on shores. South Carolina to Florida and Texas. Summer and fall. 

2*. Eleochaiis tdrtilia (Link) Schult. Annual. Scapes tufted, filiform, sharply 3- 
angled, pale green, erect or reclining, twisting when old, 3-4 dm. long : sheaths obliquely 
truncate, 1-toothed : spikelet ovoid or oblong, rather acute, several-flowered, 4-6 mm. long, 
about 2 mm. thick, much thicker than the scape: scales firm, pale, ovate, mostly obtuse : 



CYPERACEAE. 185 



perianth-bristles 4-6, rigid, retrorsely barbed, about equalling the achene and tubercle : 
stigmas 3 ; achenes obovoid, nearly 1.5 mm. long, obscurely 3-angled, strongly reticulated ; 
tubercle cap-like or conic, truncate at the base, ^-i as long as the achene. 
In wet soil, near the coast, New Jersey to Florida and Texas. Summer and fall. 

25. Eleocharis tuberculosa (Michx. ) R. & S. Annual, Scapes tufted, slightly 
compressed, very slender, rather stiff, striate, bright green, 2-5 dm. tall : upper sheath 
obliquely truncate or 1-toothed : spikelet ovoid to conic-ovoid, many-flowered, 6-12 mm. 
long, nearly 4 mm. in diameter : scales broadly ovate, obtuse, pale greenish brown with 
darker midveins, broadly scarious-margined, firm, tardily deciduous: perianth-bristles 6, 
rigid, downwardly or rarely upwardly barbed, about as long as the achene and tubercle : 
stigmas 3: achenes obovoid, 1.5 mm. long, pale, 3-angled, strongly reticulated ; tubercle 
cap-like or conic, as large as the achene or larger. 

In wet soil, mostly near the coast, Massachusetts to Pennsylvania, Florida and Texas. Summer 
and fall. 

26. Eleocharis Torreyina BoeckL Annual. Scapes filiform, densely tufted, some- 
what 4-sided, erect or reclining, sometimes proliferous by developing secondary scapes in 
the axils of the spikelet, sometimes rooting at the summit, 2-20 cm. long : upper sheath 
obliquely truncate : spikelet oblong, subacute, terete or nearly so, many-flowered, 3-6 
mm. long: scales ovate, acute, brownish red with green midveins and lighter margins, 
early deciduous except the lowest, which is commonly larger than the .others, persistent 
and bract-like : perianth-bristles 3-6, slender, shorter than the achene or equalling it : 
stigmas 3: achenes Avhite, 3-angled, obovoid, smooth, 0.7-0.8 mm. long, constricted at the 
base ; tubercle conic-pyramidal, minute. 

In wet sandy soil, southern New Jersey to Florida and Texas, mostly near the coast. Also in 
Cuba. Spring and summer. 

27. Eleocharis microcdrpa Torr. Annual, bright green. Scapes iufted, finely fili- 
form, or capillary, 5-20 cm. tall, smooth, barely constricted at the summit, spikelet ob- 
long, 2-3 mm. long, few-flow^ered, acute : scales oblong to ovate, blunt or rather acute, 
pale or with brownish patches on either side of the midrib : perianth -bristles 3-5, very 
slender, about f as long as the achene : stigmas 3 : achenes grayish white, 3-angled, ob- 
ovoid, 0.5-0.7 mm. long, smooth or nearly so ; tubercle minute, pointed. 

In wet soil, Florida to Louisiana. Also in Cuba. Spring to fall. 

28. Eleocharis prolifera Torr, Annual, sometimes aquatic, bright green. Scapes 
numerous, tufted, filiform, diffuse, or floating, flattened, 1-6 dm. long, or rarely shorter : 
spikes conic, 4-8 mm. long, rarely fruiting, acute, proliferous or rooting : scales oblong 
or oval, whitish, obtuse, thin : perianth-bristles barbed, stout, variable in length : achenes 
3 angled, obovoid, nearly 1 mm. long, surpassing the bristles ; tubercle deltoid, or depressed. 

In and about ponds and ditches. North Carolina to Florida and Lousiana. Spring to falL 

29. Eleocharis Baldv7inii (Torr.) Chapm. Perennial by slender rootstocks. Scapes 
filiform, tufted, diffusely spreading, 0.5-2 dm. long, grooved : spikelet oblong, 4-6 mm. 
long, flattened, 3-5-flowered, commonly rooting and proliferous : scales 2-ranked, 4-6, 
lanceolate, blunt or acutish, delicately nerved : perianth-bristles 4-6, unequal : achenes 
3-angIed, oblong, 1 mm. long, as long as the longer bristles ; tubercle 3-angled, abruptly 
subulate-tipped, about J as long as the body of the achene. 

In sandy swamps, Georgia and Florida. Spring to fall. 

30. Eleocharis melanocdrpa Torr. Perennial by short rootstocks. Scapes flat- 
tened, striate, tufted, slender, erect, 2-5 dm. tall : upper sheath truncate, 1-toothed : spike- 
let oblong or cylindric-oblong, obtuse, 6-12 mm. long, 3-4 mm. in diameter, many-flow- 
er^d, thicker than the scape : scales ovate, obtuse, brown, with lighter midveins and 
scarious margins : perianth-bristles 3 or 4, fragile, downwardly hispid, equalling or longer 
than the achene, fugacious or perhaps sometimes wanting ; stigmas 3 : achenes 3-angled, 
obpyramidal, fully 1 mm. long, black, smooth ; tubercle depressed, covering the summit 
of the achene, light brown, pointed in the middle. 

In wet sandy soil, eastern Massachusetts and Rhode Island to Florida, near the coast. Also in the 
West Indies. Summer and fall. 

31. Eleocharis dlbida Torr. Annual. Eoots fibrous : scapes very slender, tufted, 
nearly terete, striate, erect, 1-2 dm. tall : upper sheath very oblique and toothed on one 
side : spikelet ovoid-globose or oblong, obtuse, 4-8 mm. long, 3-4 mm. in diameter, many- 
flowered, thicker than the scape : scales pale green or nearly white, rather firm, ovate, 
obtuse, deciduous : perianth-bristles about 6, downwardly barbed, persistent, as long as 
the achene : stigmas 3 : achenes broadly obovoid, fully 1 mm. long, nearly black when 
ripe, 3-angled, smooth ; tubercle ovoid-conic, contractea or truncate at the base, about J 
as long as the achene. 

In wet soil. Maryland to Florida, Texas and Mexico, near the coast. Spring and summer.— J?, o/- 
ofda Berlandilri (Clarke) Britton, a variety native of southeastern Texas, is stouter, has longer spikelets 
and the tubercle is more beak-like. 



186 



CYPERACEAE 



32. Eleocharis tricost^ta Torr. Perennial by short rootstocks. Scapes very slender, 
erect, compressed, striate, 3-6 dm. tall : upper sheath obliquely truncate, toothed on one 
side: spikelet oblong, becoming oblong-cylindric, obtuse, many-flowered, 10-18 mm. long, 
2-3 mm. in diameter : scales ovate, thin, deciduous, obtuse, brown wuth green midveinsand 
scarious margins : perianth -bristles none : stigmas 3: achenes obovoid, 0.8-1 mm. long, 
3-angled, brown, dull, papillose, with the three angles strongly ribbed ; tubercle conic, 
acute, light brown, constricted at the base, minute, very much shorter than the achene. 

In wet soil, southern New York to Florida. Summer and fall. 

33. ZSleocharis tenuis (Willd. ) Schult. Perennial by rootstocks. Scapes tufted, 
filiform, mostly erect, 4-angled with concave sides, 2-4 dm. tall : upper sheath obliquely 
truncate, toothed an one side : spikelet narrowly oblong, mostly acute, many-flowered, 
thicker than the scape, 6-10 mm. long, about 2 mm. in diameter : involucral bract 1 : 
scales thin, obovate or ovate-oblong, obtuse, the midvein greenish, the margins scarious : 
perianth-bristles 2-4, shorter than the achene, fugacious or wanting ; stigmas 3 : achenes 
obovoid, about 1 mm. long, obtusely 3-angled, yellow to brown, irregularly ridged-reticu- 
lated or papillose, more or less persistent on the rachis of the spikelet after the scales have 
fallen ; tubercle conic, short, acute. 

In wet soil, Cape Breton Island to Ontario, Manitoba. Florida and Texas. Spring and summer. 

34. Eleocharis arenicola Torr. Perennial by horizontal rootstocks. Scapes very 
slender, tufted, 1.5-4-5 dm. tall, grooved, mostly erect : spikelets oblong to ovoid-oblong, 
4-12 mm. long, 2.5-3.5 mm. thick, many-flowered : scales oblong or ovate, thin, blunt, 
each with a brown apex and whitish margins : perianth-bristles 6, persistent, the longer as 
long as the achene : achenes 3-angled, about 1 mm. long, oblong-obovoid or obovoid, faintly 
reticulated ; tubercle thick, deltoid. 

On sandy shores and in swamps, Soutli Carolina to Florida and Texas. Spring to fall. 

35. Eleocharis acuminata (Muhl. ) Nees. Perennial by stout rootstocks, similar to 
the next preceding species but stouter. Scapes flattened, striate, slender but rather stiff, 
tufted, 2-5 dm. tall : upper sheath truncate, sometimes slightly 1 -toothed : spikelet ovoid 
or oblong, obtuse, thicker than the scape, many-flowered, 6-12 mm. long : scales oblong or 
ovate-lanceolate, acute, purple-brown with greenish midveins and hyaline white margins, 
deciduous: perianth-bristles 1-5, shorter than or equalling the achene, fugacious, or want- 
ing : stigmas 3, exserted : achenes obovoid, 1,5 mm. long, obtusely 3-angled, light yel- 
lowish brown, papillose, much longer than the depressed conic acute tubercle, persistent 
on the rachis as in E. tenuis. 

In wet soil, Anticosti to Manitoba, Georgia, Louisiana and Nebraska. Summer. 

36. Eleocharis cylindrica Buckl. Perennial by slender rootstocks. Scapes very 
slender, tufted: spikelets linear-cylindric, or slightly flattened, 1-2 cm. long, about 3 mm. 
thick, acutish, many-flowered : scales various, the lower ovate and blunt, the upper ovate 
or oblong-lanceolate and acute, with whitish hyaline margins : perianth-bristles wanting : 
achenes obovoid, fully 0.5 mm. long, yellowish, constricted at the ends but especially under 
the acute tubercle. 

F 

In sandy soil, Texas. Summer and fall. 

37. Eleocharis rostell^ta Torr. Perennial by a short caudex. Scapes slender, wiry, 
the fertile ones erect or ascending, the sterile reclining and rooting at the summit, grooved, 
3-15 dm. long : upper sheath truncate : spikelet oblong, narrowed at both ends, thicker 
than the scape, 10-20-flowered, 6-12 mm. long, about 2 mm. in diameter : scales ovate, 
obtuse or the upper acute, green with somewhat darker midveins : perianth-bristles 4-8, 
retrorsely barbed, longer than the achene and tubercle : stigmas 3 : achenes oblong-ob- 
ovoid, 1.5 mm. long, obtusely 3-angled, their surface finely reticulated; tubercle conic- 
subulate, about J as long as the achene or shorter, capping its summit, partly or entirely 
falling away at maturity. 

In marshes and wet meadows, New Hampshire to Vermont and western New York, British Colum- 
bia, Florida, Texas, Mexico and California. Also in Cuba. Summer and fall. 



11. FIMBRISTYLIS Vahl. 



Annual or perennial scapose herbs. Spikelets umbellate or capitate, terete, several to 
many-flowered, subtended by a 1-many-leaved involucre, their scales spirally imbricated 
all around, mostly deciduous, all fertile. Perianth none. Stamens 1-3. Style pubescent 
or glabrous, its base usually much enlarged, but falling away from the summit of the 
achene at maturity. Stigmas 2-3. Achenes lenticular, biconvex, or 3-angled, reticulated, 
cancellate, or longitudinally ribbed or striate. The plants flower mainly in summer and fall- 



CYPERACEAE 



187 



2. F, spadicea, 

3. F, caitanea, 

4. F. IJrummondiL 

5. F. laxa, 

6. F. Vahlii, 



Style-branches or stigmas 2 : achenes lenticular, 

Spikelets peduncled, forming umbels, or solitary and sessile. 
Perennial : leaf-blades strongly involute. 

Bracts of the involucre shorter than the spikelets. 1. F, schoenoides. 

Bracts of the involucre or some of them longer than the spikelets. 
Base of the style swollen. 
Scales coriaceous, shining. 
Scales thinner, dull. 
Base of the style not swollen. 
Annual : leaf-blades flat or nearly so. 
Spikelets several, sessile, forming a terminal head. 
Scales acuminate : achenes obovoid. 
• Scales subulate-tipped : achenes oblong-cylindric. 7. F. pcrpxmlla. 

Style-branches or stigmas 3: achenes 3-angled. 

Spikelets narrow, or if relatively thick, in simple'umbels. 

Umbel mostly simple : spikelets ovoid or oval, blunt: achenes distinctly 

reticulated . 
Umbel mostly compound : spikelets linear-oblong, acute : achenes smooth or 

indistinctly reticulated. 9. F, autumnalis, 

Spikelets globular or about as thick as long, in decompound umbels. 10. F. miliacea, 

1. Fimbriatylis schoenoides Vahl. Perennial, glabrous. Leaves erect or nearly 
so : blades attenuate from the slightly dilated bsaes, involute : scapes more or less densely 
tufted, 1-4 dm. tall, mostly overtopping the leaves, smooth : bracts of the involucre shorter 
than the spikelets, inconspicuous : spikelets solitary, or 2 or 3 together forming an umbel, 
and the earliest one sessile, ovoid or conic-ovoid, 5-12 mm. long, 3-4 mm. thick, pale 



8. F. F-ankiL 



brown : scales rather blunt, firm : stigmas 2 : achenes lenticular, broadly obovoid, barely 
1.5 mm. long, lustrous, whitish, not pointed. 

In low grounds, Florida. Also in tropical Asia. 

2. Fimbristylis spadicea (L.) VahL Perennial by a thickened base, glabrous. 
Leaves few : blades about 2 mm. wide ^vhen unrolled, their sheaths dark brown : scapes 
stiff, slender, 3-angled, wiry, tall, usually longer than the strongly involute, rigid leaves : 
bracts of the involucre 3-6, erect : umbel several-rayed, the rays nearly erect, 5-15 cm. 
long : central spikelets of the umbels and umbellets sessile, the others pedicelled : spikelets 
ovoid or ovoid-cylindric, acute, 5-12 mm. long, about 2 mm. in diameter : scales oval, 
obovate, or orbicular, obtuse or subacute, coriaceous, glabrous, shining, dark brown with 
green midribs: stigmas 2: achenes lenticular, obovoid, 1.5 mm. long, brown. 

In marshes and shallow water, Virginia to Florida, near the coast. Widely distributed in tropical 
America. 

3. Fimbristylis cast^nea (Michx.) VahL Perennial by a thick base. Leaves few ; 
blades involute, less than 2 mm. wide, their sheaths green and more or less pubescent : 
scapes slender, 3-angled, 2-5 dm. tall, usually exceeding the leaves: bracts of the invo- 
lucre 2-4, short : umbel simple or compound, the rays 1-5 cm. long : the central spike- 
lets sessile: spikelets oblong, 6-10 mm. long, 2-3 mm. in diameter: scales thin, brown 
with lighter midveins, broadly oblong or nearly orbicular, dull, puberulent, obtuse or 
mucronate: stigmas 2: achenes obovoid or oblong, about 1.5 mm. long, biconvex, pale 
brown, that of the prairie plant is shorter and less tapering to the base. 

On salt meadows, southern New York to Florida and Louisiana. Also in Avet soil in the interior 
from Ontario, Michigan and Illinois to Kansas and Texas, and in tropical America— A variety with 
copiously pubescent leaves and scapes, is F, castanea pub^rula (Michx.) Britton. It ranges from Georgia 
and Florida to Texas. 

4. Fimbristylis Drummdndii (Torr. & Hook.) Britton. Perennial, glabrous. 
Leaves rather stiff ; blades attenuate from the slightly dilated base, convex beneath, 
scarcely 2 mm. wude : scapes erect, somewhat tufted, about 9 dm. tall, twice as long ag the 
leaves, smooth, deeply channeled on one side : bracts of the involucre 2-3, shorter than 
the inflorescence : umbel compound, with 4-6 curved rays 2-5 cm. long : spikelets oblong- 
ovate, about 12 mm. long, 3-5 mm. broad, pale brown, acute: scales mucronulate, rigid, 
slightly keeled near the apex : style not thickened at the base : stigmas 2 : achenes lenticular, 
obovoid, about 1.5 mm. long, apiculate at the apex. {holepU Drumniondii Torr. & Hook.] 

In low grounds, Texas. 

5. Fimbristylis Idza Vahl. Annual, glabrous or sparingly ciliate. Leaves pale 
green ; blades flat, about 1 mm. wide : scapes slender, flattened, striate, densely tufted, 
erect or ascending, 5-40 cm. long, usually longer than the leaves : bracts of the involucre 
3-5 : umbel simple or slightly compound, the central spikelets sessile : spikelets ovoid or 
ovoid-oblong, 6-12 mm. long, about 2 mm. in diameter: scales ovate, thin, pale greenish 
brown, subacute or mucronulate : stigmas 2: achenes biconvex, obovoid, fully 1 mm. long, 
brown, longitudinally ribbed, the ribs tubercled and connected by very fine cross lines. 

In moist soil, southern Pennsylvania to Missouri, Florida and Texas. Also in tropical America. 

6. Fimbristylis Vahlii (Lam.) Link. Annual. Leaves setaceous or almost filiform, 
rough : scapes very slender, densely tufted, compressed, striate, 2-10 cm. high, longer than 
or equalling the leaves : bracts of the involucre 3-5, erect, much exceeding the simple 



188 



CYPERACEAE 



r 

capitate cluster of 3-8 spikelets : spikelets oblong-cylindric, obtuse, 4-8 mm. long, about 
1 mm, thick, many-flowered : scales lanceolate, pale greenish brown, acuminate : stigmas 2 : 
achenes obovoid, about 0.5 mm. long, biconvex, yellowish white, cancellate. 

In moist soil, Msssouri to Texas, North Carolina and Florida. 

7. Fimbristylia perpusilla Harper. Annual. Leaves few, basal, filiform, rather 
shorter than the scapes : scapes in small prostrate radiating tufts, 1-3 cm. long : bracts of 
the involucre few, mostly less than 1 cm. long : spikelets globular, 1-2 mm. in diameter, 
sessile or nearly so during anthesis : scales green or yellowish, each tapering into a loosely 
spreading awn : stamen 1 : stigmas 2 : achene oblong-cylindric, about 0.5 mm. long. 

In pine-land ponds, near Leslie, Georgia. Fall. 

8. Fimbristylls Prdnkii Steud. Annual, lower than the next following species, the 
leaves often shorter. Umbel mostly simple, the spikelets, or most of them, capitate and 
sessile, ovoid or oval, blunt, the heads sometimes appearing almost sessile at the base : 
achenes 0.5 mm. long, distinctly reticulated. 

In mud or wet sand, New Hampshire to Missouri, Tennessee and Louisiana. 

9. Fimbristylis autumnklis (L. ) R. & S. Annual. Leaves glabrous; blades nar- 
rowly linear, flat, 1-2 mm. wide : scapes very slender, densely tufted, flat, 7-40 cm. long, 
usually mucli exceeding the leaves : bracts of the involucre 2-3, usually all shorter than 
the umbel : umbel compound or decompound, the primary rays 4-10 mm. long, the secon- 
dary filiform : spikelets linear oblong, acute, 6-40 mm. long, 1 mm. thick or less : scales 
ovate-lanceolate, subacute, strongly mucronate, greenish brown, the midvein prominent : 
stigmas 3 : achenes obovoid, about 0.5 mm. long, nearly white, 3-angled with a ridge on 
each angle, smooth or indistinctly reticulated, sometimes roughened. 

In moist soil, Maine to Michigan, Florida, Louisiana and Texas. Also In tropical America. 
Summer and fall. 

10. Fimbristylls miMcea Vahl. Annual (always?), glabrous. Leaves rather tender ; 
blades ensiform, long-attenuate: scapes weak, often loosely tufted, 1.5-6 dm. tall, mostly 
overtopping the leaves, smooth : bracts of the involucre shorter than the inflorescence : 
umbel erect, decompound, its peduncles often filiform ; spikelets several or numerous, ovoid 
or globular, 2-3 mm. long, blunt, pale brown : scales blunt, with broad midnerves : stig- 
~ "s 3 : achenes 3-angled, obovoid, less than 1 mm. long, minutely roughened, pale. 

In bogs and ditches, Florida. Widely distributed in the tropics. Spring to fall. 

12. STENOPHYLLUS Raf. 
Mostly annual herbs, with slender erect scapes. Leaves basal : blades narrowly linear 
or filiform, the sheaths ciliate or pubescent. Spikelets umbellate, capitate or solitary, sub- 
tended by an involucre of 1-several bracts, their scales spirally imbricated, mostly decidu- 
ous. Flowers perfect. Perianth none. Stamens 2 or 3. Style glabrous, its base much 
swollen and persistent as a tubercle of the achene as in Eleocharis. Stigmas 2-3. Achene 
3-angled, turgid or lenticular. 

Spikelets in open umbels or sometimes solitary. 

Leaf-blades serrulate-ciliate : umbel noc contracted : spikelets 5-8-flowered. 

Umbel simple : scales of the spikelets obtuse : achene transversely wrinkled. 1. S. capillaris. 
Umbel compound : scales of the spikelets acute : achene minutely papillose. 2. S. cUiatifolius. 
Leaf-blades smooth and glabrous : umbel contracted : spikelets 10-15-nowered. 8. 5. coarctatus. 
Spikelets clustered in terminal heads. 

Bracts of the involucre with entire bases. 

Scales mucronate: involucral bracts few, short. - 4. S. Floridanug, 

Scales subulate-tipped : bracts very long, much exceeding the heads. 5. S. StenophyUus. 

Bracts of the involucre with fimbriate bases. 6. S, Ward. 

1. StenophyUus capillaris (L. ) Britton. Leaves roughish, much shorter than the 

scape, their sheaths more or less pubescent with long hairs : scapes filiform, densely tufted, 

erect, grooved, smooth, 5-25 cm. tall : involucral bracts 1-3, setaceous : spikelets narrowly 

oblong, somewhat 4-sided, 5-8 mm. long, less than 2 mm. thick, several in a terminal tim- 

bel, or in depauperate forms solitary : scales oblong, obtuse or emarginate, puberulent, 

dark brown with green keels : stigmas 3 : achenes yellow-brown, narrowed at the base, very 

obtuse or truncate at the summit, nearly 1 mm. long, transversely wrinkled ; tubercle 

minute, depressed. [Fsolepis capiilaris (L. ) R- & S.] 

In drj'or moist soil, throughout North America, except the extreme north. Also in!tropicaI Amer- 
ica. Summer and fall. 

r 

2. StenophyUus ciliatif61ius (Ell.) C. Mohr. Leaves erect ; blades bristle-like or 
linear-filiform, channeled, serrulate-ciliate : scapes tufted, very slender, 10-30 cm. tall, 
often slightly scabrous near the top : bracts of the involucre 2-3, similar to the leaves but 
shorter, one about as long as the umbel, the others very short : spikelets numerous in a ter- 
minal compound umbel, linear-oblong, 2-4 ram. long, acute, 6-12-flowered : scales broad, 
brown-margined, keeled, abruptly pointed, often ciliate toward the apex : achenes 3-angled, 



CYPERACEAE 



189 



obovoid, less than 1 mm. long, bluish, minutelv papillose, [/so/ep/s cilUiiifolia (Ell.) 
Torr]. 

In pine lands, North Carolina to Florida and Alabama. Spring to fall. 



3. Stenophyllus coarctitus (Ell.) Britton. Leaves few ; blades bristle-like, glabrous 
or nearly so ; sheaths bearded at the mouth : scapes tufted, filiform, about 30 cm. long, 
arching, smooth : bracts of the involucre several, only one as long as the umbel or slightly 
longer : spikelets several, linear-oblong, about 6 mm. long, sessile or short-peduncled, 10- 
15-nowered : scales ovate, acutish, with reddish margins, ciliate near the apex : achenes 
unequally 3-angled, the inner face broadest, about 1 mm. long, minutely papillose ; tubercle 
a minute black tip. \_holepis coaretata (Ell.) Torr.] 

In dry sandy soil, Georgia and Florida. Summer and fall. 

4. Stenophyllus Florid^nus Britton. Leaves much surpassed by the scapes ; blades 
filiform, erect, ^ as long as the scapes or shorter; sheaths ciliate : scapes tufted, filiform, 
10-20 cm. tall : spikelets linear or nearly so, 4-8 mm. long, about 1 mm. thick, acute, rich 
brown, 4-10 sessile in dense terminal heads : scales ovate-lanceolate, about 1 mm. long, 
keeled, each prolonged into a minute slightly spreading tip : achenes 3-angled, broadly 
obovoid, pale. 

In high pine lands, southern Georgia and Florida. Summer. Water-grass. 

5. Stenophyllus Stenophyllus (Ell.) Britton. Leaves numerous, overtopped by 
the scape ; blades filiform or bristle-like, erect, bristly-ciliate : scapes densely tufted, 5-20 
cm. tall, scabrous at least above : bracts of the involucre several, 3 or 4 much longer than 
the rest, ciliate like the leaf-blades, the dilated bases never fimbriate : spikelets 4-8, sessile 
in dense terminal heads, about 5-7 mm. long, 6-10-flowered : scales variable in length, 
loosely imbricated, hispid on the 3-nerved keel, produced into a cuspidate tip : achenes 3- 
angled, obovoid, about 1 mm. long, bluish white, transversely wrinkled ; tubercle minute, 
persistent, llsolepis stenophylla (Ell.) Torr.] 

In dry sandy soil. North Carolina to Florida and Louisiana. Spring to fall, 

6. Stenophyllus "Wkrei (Torr.) Britton. Leaves shorter than the scape; blades 
bristle-like, channeled ; sheaths pectinately fringed at the mouth. Scapes densely tufted, 
20-40 cm. tall, filiform, slightly flattened, smooth and glabrous : bracts of the involucre 
3-4, about twice as long as the head, rigid, the broadly dilated bases fimbriate : spikelets 
8-15 in a compact head, ovoid, 6-7 mm. long, 10-15-flowered : scales broad, mucronate, 
ciliate-pubescent without : achenes 3-angled, obovoid, white, obscurely wrinkled ; tubercle 
minute, dark-colored, [Isolepis TTareiTorr.] 

In dry sand, Florida. Spring to fall. 

13. PSILOCARYA Torr, 

Annual herbs, with fibrous roots, slender stems and ovoid or oblong, many-flowered 

terete spikelets in terminal and axillary, mostly compound umbels, the rays and raylets 

bracted at the base. Scales of the spikelets spirally imbricated, all fertile, deciduous. 

Flowers perfect. Perianth none. Stamens 1 or 2. Style enlarged at the base. Stigmas 2. 

Achene lenticular or biconvex, smooth or transversely wrinkled, capped by the persistent 

base of the style (tubercle), or nearly the whole style persistent as a beak. 

Scales of the spikelets acute or acuminate : tubercle less than % as long as the achene. 

1. P. nitens. 
Scales of the spikelets blunt : tubercle over J^ as long as the achene. 2. P. corymbi/ormis, 

1- Psilocarya nitens (Vahl) Wood. Stems tufted, slightly angled, 7-40 cm. tall: 
leaves sometimes overtopping the stem, sheathing at the base ; blades narrowly linear, 
about 2 mm. wide, smooth, the midvein prominent : umbels mostly loose : spikelets ovoid, 
4-6 mm. long, rather less than 2 mm. in diameter : scales brown, broadly ovate, thin, 1- 
nervedj obtuse, acute or apiculate : achenes lenticular, nearly orbicular, nearly 1.5 mm, 
long, light brown, strongly transversely wrinkled ; tubercle ghorter than the achene-body, 
subacute, 2-lobed at the base. 

In wet soil, near the coast, Long Island and Delaware to Florida and Texas. Summer and fall. 

2. Psilocarya corymbifdrmls Benth, Stems solitary or sparingly tufted, 2-7 dm. 
tall, topped like the branches by a corymb : leaves several, mostly overtopped by the stems ; 
blades more or less involute above the sheath, 2-6 cm. broad, attenuate : spikelets in lax 
corymbs, oblong-ovoid, 6-10 mm. long, fully 2 mm, thick: scales brownish, narrowly 
ovate or ovate-lanceolate, thinner than in the preceding, blunt : achenes lenticular, sub- 
orbicular, 0.5 mm. long, including the slightly decurrent tubercle, this nearly as long as 
the body of the achene. 

In low pine lands, Georgia and Florida to Louisiana. Also In the West Indies. Spring to fall. 



190 



CYPERACEAE 



14. DICHROMENA Michx. 

Leafy-stemmed sedges, perennial by rootstocks, the spikelets crowded in a terminal 
head involucrate by several bracts, which are often white at the base, Spikelets compressed, 
several-many-flowered. Scales spirally imbricated all around, several of them with imper- 
fect flowers, or empty. Perianth none. Stamens 3- Style subulate. Stigmas 2, very 
slender. Achene lenticular, transversely rugose, crowned with the broad persistent base 
of the style (tubercle). The plants bloom from spring to fall. White-top. 

Involucre of 2 bracts : achenes barely 1 mm. long. • 1. D. nivea. 

Involucre of 4-10 bracts : achenes over 1 mm. long. 

Bracts of the involucre 4-6, linear: tubercle truncate on top of the achene. 

Leaves tiliform above the dilated base : achenes dark ; tubercle low, blunt. 2. P. Floridensis. 

Leaves linear above the dilated base : achenes pale ; tubercle long, acute. 3. D. colorata. 

Bracts of the involucre 7-10, lanceolate : tubercle decurrent on the sides of the 

achene. 4. D. latifoUa, 

1. Dichromena nfvea Boeckl. Stems tufted, 1-3 dm. tall, very slender nearly terete, 
smooth : leaves mostly shorter than the stems ; blades very narrowly linear or linear-fili- 
form : bracts of the involucre 2, very unequal, slender beyond the white dilated bases : 
head less than 1 cm. in diameter, pearly white, erect : spikelets ovate, 3-4 mm. long, 
crowded : scales smooth, notched at the apex, closely imbricated : achenes lenticular, 
plump, obovoid, barely 1 mm. long, short-beaked, with prominently wrinkled sides. 

In wet soil and low grounds, Arkansas and Texas. 



2. Dichromena Florid^nsis Britton. Stems copiously tufted, 2-4 dm. tall, smooth, 
slender : leaves numerous ; blades involute-filiform, smooth : bracts of the involucre 4-6, 
slenderly attenuate : heads about 1 cm. in diameter : spikelets oblong : scales pale : achenes 
obovoid, slightly over 1 mm, long, dark brown, finely wrinkled, the tubercle nearly trun- 
cate on the top of the achene-body. 

In low pine lands, southern Florida. 

3. Dichromena color §ita ( L. ) A. S. Hitchcock. Stem slender, rather sharply tri- 
angular, 3-6 dm. tall. Leaf-blades narrowly linear, much shorter than the stem : bracts 
of the involucre 4-6, reflexed when mature, yellowish white at the base : head globose, 
1-2 cm. in diameter : spikelets narrowly oblong, acute ; scales membranous, lanceolate, 
nearly white, 1 -nerved, subacute : achenes obovoid, a little over 1 mm. long, excluding 
the tubercle, pale brown, compressed, nearly truncate at the summit, there covered by the 
tubercle which is not decurrent on its edges. [D. leucocephala Michx.] 

In moist sandy soil, pine lands, New Jersey to Florida and Texas. Also in tropical America. 

4. Dichromena latifolia Baldw. Similar to the next preceding species but the stem 
stouter, obtusely triangular or nearly terete. Leaf-blades lanceolate or linear-lanceolate, 
tapering gradually to a long acuminate apex from a broad base, 3-8 mm. wide, sometimes 
overtopping the stem, but the lowest much shorter : bracts of the involucre 7-10, strongly 
reflexed when old : head globose, 1-2 cm. in diameter : spikelets oblong, subacute : scales 
ovate-lanceolate, nearly white, rather obtuse : achenes nearly orbicular in outline, a little 
over 1 mm, long, excluding the tubercle, pale brown, faintly wrinkled transversely and 
longitudinally so as to appear reticulated ; the tubercle decurrent on its margins. 

In wet pine lands, Virginia to Florida and Texas. 

15. ABILDGAARDIA Vahl. 

Perennial, or sometimes annual, acaulescent herbs. Leaves basal : blades narrow, 
commonly involute : scapes tufted, jointless, simple. Involucre of a single small bract. 
Spikelets solitary or several in terminal umbels or clusters, several to many-flowered : 
scales imbricated in 2 rows, or in 3 rows by the twisting of the rachis, keeled, decurrent, 
deciduous. Perianth wanting. Stamens 1-3. Style pubescent, with a swollen base, de- 
ciduous. Stigmas 3. Achenes 3-angled, broadest above the middle, warty, pale. 

1. Abildgaardia monost&chya (L. ) Vahl, Perennial, glabrous. Leaves firm, 
shorter than tlie scape ; blades nearly filiform above the discolored bases, slightly involute, 
sharp-pointed : scapes tufted, very slender or filiform, 1-4 dm. tall, erect, smooth : bracts 
of the involucre much shorter than the spikelets, inconspicuous : spikelet solitary or some- 
times 2 together, flattened, ovoid or conic, 1-1.5 cm. long, pale : scales in 2 rows, acute or 
mucronulate, with broad white margins : stigmas 3 : achenes slightly pear-shaped, 2-2.5 
mm. long, constricted near the base, copiously warty, yellowish white, often apiculate. 

In sandy or rocky soil, peninsular Florida and the Keys. Also in the tropics. Spring to fall. 

r" 

16. SCHOENUS L. 

Perennial rush-like herbs, with tufted rigid scapes. Leaves basal ; sheath dark -col- 



CYPERACEAE 



191 



ored ; blades resembling the scapes, half-terete. Spikes in a terminal cluster, 1-8-flowered, 
subtended by an involucre of 1-2 bracts. Spikelets crowded, often dark-colored : scales 
imbricated in 2 rows, the lower ones empty, the upper flower-bearing. Perianth of 3-6 
scabrous or plumose hiistles- Stamens 3. Style barely enlarged at the base, almost wholly 
deciduous. Stigmas 3. Achene 3-angled, without a tubercle. IChaetospora R. Br.] 

1. Schoenus nigricans L. Foliage glabrous. Leaves basal ; sheaths dark brown or 
almost black at the base ; blades overtopped by the scape, erect, rigid, pungent : scapes 
tufted, 2-6 dm. tall : bracts of the involucre 2, the lower one surpassing the infloreseence : 
head about 1 cm. long, dark chestnut-colored : spikelets flattened, 6-8-flowered, narrowed 
upward : scales ovate or lanceolate-ovate, firm, keeled : perianth-bristles 6, unequal, some- 
what plumose: achenes oval, white and polished, about 2 mm. long, surpassed by the 
bristles. IChaetospora nigricans (L. ) Kuntn.] 

In damp sandy soil, Florida to Texas and California. Also in the Old World. 

17. CLADIUM P. Br. 

Perennial leafy herbs, similar to the Runchosporae in habit. Spikelets oblong or fusi- 
form, few-flowered, variously clustered. Scales imbricated all around, the lower empty, 



the middle ones mostly subtending imperfect flowers, the upper usually fertile. Perianth 
none. Stamens 2, or sometimes 3. Style deciduous from the summit of the achene. Stig- 
mas 2-3. Achene ovoid to globose, smooth or longitudinally striate : tubercle none. 

Leaf-blades about 2 ram. wide ; umbels small : achene truncate at the base. 1, C. mariscoides. 

Leaf-blades 6-20 mm. wide : umbels large, panicled : achene narrowed to the base. 2. C. cffusum, 

1, Cladlum maii^coides (Muhl. ) Torr. Stems 3-9 dm. tall, slender, rather stiff, 
obscurely 3-angled, smooth : leaves about 2 mm. wide, concave, with long compressed tips, 
nearly smooth : umbels 2 or 3, compound, small: spikelets oblong, narrowed at both ends, 
acute, 5 mm. long, capitate on the raylets : scales chestnut-brown, ovate or ovate-lanceo- 
late, acute ; upper scale subtending a perfect flower with 2 stamens and a filiform style and 
3 stigmas, the next lower one with 2 stamens and an abortive ovary : achene ovoid, acute, 
finely longitudinally striate, about 2 mm. long. 

In marshes, Nova Scotia to Minnesota, Florida and Kentucky. Pond Rush. Twig RrsH. 

2. Cladium effusum (Sw. ) Torr. Stems stout, 1.5-3 m. high, obtusely 3-angled: 
leaves very long, glabrous, 6-20 mm. wide, the margins spinulose-serrulate : umbels sev- 
eral or numerous, decompound, forming a large panicle : spikelets mostly 2-5 together at 
the ends of the raylets, narrowly ovoid, acute, 4-5 mm. long ; uppermost scale subtending 
a perfect flower : stamens 2 : achene ovoid, abruptly sharp-pointed, wrinkled, narrowed to 
the base, 2 mm. long. 

In water, Virginia to Florida and Texas. Also in the West Indies. Saw-grass. 

18. RBMIREA Aubl. 

Perennial sometimes caulescent herbs, with horizontal rootstocks. Stems more or less 
tufted, relatively low. Leaves imbricated : blades narrow, rigid. Involucre with numerous 
bracts, the outer spreading. Flowers perfect. Spikelets numerous, crowded into a single 
terminal head, sessile, 1-flowered. Scales about 4, imbricated, the lower one empty. Sta- 
mens 3. Perianth wanting. Style barely enlarged below, the base continuous w^ith the 
ovary. Stigmas 3. Achenes 3-angled, tightly enclosed in the inner scales. Tuft-grass. 

1. Remirea marltiina Aubl. Foliage glabrous, bright green. Stems erect, 0.5-3 
dm. tall, densely leafy, simple : leaves numerous ; blades linear or linear-lanceolate, 2-10 
cm. long, attenuate, slightly involute, smooth : bracts of the involucre resembling the 
leaves: spike 1-1.5 cm. long, ovoid, sometimes compound: spikelets 3-5 mm. long: 
achenes narrowly oblong, 2.5-3 mm. long, often curved, apiculate, rather granular. 

On sandy beaches, peninsular Florida. Also widely distributed in the tropics. Spring to fall. 

19. RYNCHOSPORA Vahl. 

Caulescent herbs, mostly perennial by rootstocks, with 3-angled or terete stems, nar- 
row, flat, or involute leaf-blades, and ovoid oblong or fusiform, variously clustered spikelets. 
Scales thin, 1-nerved, imbricated all around, usually mucronate by the excurrent midvein, 
the lower empty. Upper flowers imperfect, the lower perfect. Perianth of 1-24 (mostly 
6) upwardly or downwardly barbed or scabrous bristles, or wanting in some species. 
Stamens commonly 3. Stigmas 2, rarely wholly united. Achene lenticular or swollen, 
not 3-angled, smooth, cancellate or transversely wrinkled, capped with the persistent base 
of the style (tubercle), or in some species by the whole style. Beak Rush. 



192 



CYPERACEAE 



style long, its branches much shorter than the united lower part. 
Spikelets in 1-4 dense globose heads. . 

Achene truncate, tipped by a subulate tubercle, ciliate. 
Aehene obovoid, tipped by a conic tubercle, not ciliate. 
Spikelets in panicled clusters : achene capped by a stout tubercle. 

Mature spikelets about I cm. long : tubercle slightly longer than the achene. 
Mature spikelets much over 1 cm. long : tubercle several times longer than 
the achene. 
Style short, its branches as long as the united part or longer. 
Perianth-bristles none or very short. 
Achene transversely wrinkled. 
Achene smooth or reticulated. 

Achene reticulated, 0.5-0.7 mm. long : spikelets loosely corymbose. 
Achene smooth, 1.5-2 mm. long : spikelets corymbose-capitate. 

Stem-leaves with blades 0.7 mm. wide or less : spikelets 3-4 mm. long. 
Stem-leaves with blades 1.5-2.5 mm. wide : spikelets 4-6 mm. long. 
Perianth-bristles present and usually well developed. 
Bristles plumose: achene wrinkled. 

Spikelets solitary or 2-4 together. 6-8 mm. long. 
Spikelets numerous, clustered, 2.5-4 mm. long. 

Perianth-bristles plumose nearly or quite to the top. 
Stems slender, 1.5-3.5 dm, tall : spikelets small. 
Stems stout, 3-6 dm tall : spikelets large. 
Perianth-bristles plumose below the middle or only near the base. 
Bristles not plumose. 

Bristles retrorsely barbed. 

Scales pale green or white: perianth-bristles 9-24. * 
Scales brown : perianth-bristles 6. 

Spikelets few to numerous in rather loose, often panicled clusters. 
Spikelets numerous, in 2-4 dense globose heads. 
Spikelets 5-6 mm. long : achene 2.5 mm. long. 
Spikelets 3-3.5 mm. long : achene 1.5 mm. long. 
Bristles upwardly barbed. 

Achene smooth or cancellate, not transversely wrinkled. 
Achene smooth. 

Tubercle of the achene ciliate to serrulate. 
Leaf-blades flat. 
Leaf-blades channeled, involute, filiform or nearly so. 

Achene linear-oblong : perianth-bristles much overtopping 

the tubercle. 
Achene obovoid : perianth-bristles not longer than the 
achene and tubercle, or scarcely so. 
Achene 1 mm. long or less, light brown. 
Achene 1.5-2 mm. long, dark brown. 
Tubercle of the achene smooth or merely granular. 
Perianth-bristles as long as the achene or longer. 
Leaf-blades 0.5-2 mm. wide. 

Perianth-bristles about as long as the achene. 
Perianth-bristles much longer than the achene. 
Leaf-blades 2-7 mm. wide. 
Perianth- bristles much shorter than the achene, sometimes 
very short. 
Leaf-blades 0.5-3 mm. wide : spikelets 2-5 mm. long. 
Leaf-blades narrowly linear : spikelets 2-3 mm. long. 
Leaf-blades bristle-like, filiform : spikelets 4-5 mm. long. 
Leaf-blades 4-10 mm. wide : spikelets 6-8 mm. long. 
Achene cancellate. 

Leaf-blades broadly linear, blunt or merely acute: achene 1.5 
mm. long. 

Leaf-blades narrowly linear, attenuate. 

Achenes 2.5 mm, long, equalling or shorter than the bristles. 
Achenes 1.5 mm. long, much longer than the bristles. 
Achene transversely wrinkled. 

Perianth^bristles shorter than the achene. 

Leaf-blades and stems filiform : spikelets filiform-pedicelled. 

Leaf-blades not filiform, flat or involute: spikelets sessile or 
short-pedicelled. 

Leaf-blades involute. 

Achene flat, 1.5 mm. long, continuous with the tubercle. 

Achene strongly biconvex, 2 mm. long, constricted under 

the tubercle. 

Leaf-blades flat. 

Achene biconvex, not constricted under the tubercle. 

Achene 1 mm. long : tubercle depressed, wider than high. 

Achene 1.5 mm. long : tubercle conic, about as high as 

wide. 
Achene compressed, constricted under the tubercle. 
Perianth-bristles as long as the achene or longer. 
A. Spikelets ovoid to globular, 2-4 mm. long. 
a. Achene not stipitate. 
♦ Tubercle setose. 

t Spikelets 1-3-flowered. 

Perianth-bristles not longer than the achene and 

tubercle. 
Perianth-bristles longer than the achene and tubercle. 
Achene broadly or orbicular-obovoid. 
Achene narrowly obovoid. 



1. i?. TracijL 

2. R, solitdria, 

3. iJ. Indianolensis 

4. i2. corniculata. 



5. E. piiMUa, 

6. J?, divergens. 

7. E, ChajjTnanii. 

8. R. pallida. 



9. i?, oligantha. 



10. R, plumosa, 

11. iJ. intermedia. 

12. R, semiplumosa 



13. R. alba. 

14. R. glomerata, 

15. R. axillans, 

16. R, microcephala. 



17. R.fuscoides, 



18. R, Curtissil, 



19. R.fllifolia, 

20. R, leptorhyncha 



21. i?. distavs. 

22. R. gracilenia. 

23. R, Baldwinii, 



24. 
25. 

26. 



R./asdcvlaris. 
R. brachychaeta 
R. dodecandra. 



27. i?. eiliata, 

28. i?. Gravl 

29. i?. PLankil 



30. R, rariflora. 



31. i?. Torreyana 

32. R, EarleL 



33. R. perplexa, 

34. i?. cymosa. 

35. i?. compressa 



36. R, paticla. 

37. i?. caduca 

38. i?. mixta. 



C YPERACEA E 



193 



ttSpikelets5-10-flowcred. Z9. E. proUfera, 

** Tubercle not setose. 

Tubercle conic or triangular, acute, J^-K &s long as the 
achcne. 
Achene about 2 mra. long, 40. R. jyunctata, 

Achene 1-1.25 mm. long. 

Perianth-bristles not longer than the achene or but 
little longer. 
Spikelets chistered : tubercle bluntish. 41. R. microcarpa. 

Spikelets tiliform-pedicelled : tubercle sharp- 
pointed. 42. R. decurrcns. 
Perianth-bristles as long as the achene and tuber- 
cle or longer. 43. R. schocnoidcs. 
Tubercle depressed, rounded, less than J^ as long as the 

achene. 44, R. miUacea, 

b. Achene constricted at the base into a stipe : tubercle setose. 45. A*, stipitata, 
B. Spikelets fusiform to lanceolate, 4-6 mm. long. 

Leaf-blades filiform : achene obovoid : tubercle smooth. 46, R, sfcnophylla. 

Leaf-blades not filiform : achene linear-oblong or oblanceo- 

late : tubercle setose. 47. R. inexpansa, 

1. Rynchospora Tracyi Britton. Perennial, bright green. Stems tufted, 5-12 dm. 
tall, nearly terete: leaves elongated ; blades channeled, 4-8 mm. wide, straight, erect or 
ascending : spikelets densely aggregated into 1-6 globose heads 1-2 cm. in diameter, lan- 
ceolate in outline, 5-6 mm. long, acuminate, pale : scales often 9, the fourth one fer- 
tile: perianth-bristles 6, very slender: achenes flat, obovoid or cuneate-obovoid, 2.5 
mm. long excluding the tubercle, minutely Avrinkled, ciliate, surpassed by the bristles : 
tubercle subulate, fully twice as long as the achene. ICeratoschoenus capitatus Chapm., not 
-R. cajritata R. & S.] 

In pine-land ponds, Georgia and Florida to Mississippi. Spring to fall. 

2. Rynchospora solitkria R. M. Harper, Perennial or perhaps annual, light green. 
Stems solitary, 6-8 dm. tall, flattened : leaves few ; blades about 2 mm. wide, the lower 
ones about \ as long as the stem ; upper stem-leaves 1 or 2 : spikelets narrowly lanceolate, 
5-6 mm. long, 1-flowered, aggregated into a single dense terminal head 12-15 mm. in 
diameter: bracts filiform, slightly exceeding the inflorescence : perianth-bristles 6, fragile, 
equalling the achene, upwardly barbed: achenes obovoid, plump, 1.5 mm. long, faintly 
pitted, not ciliate, capped by a triangular tubercle of about | its length. 

In moist pine lands, southern Georgia. Summer and fall. 

3. Rynchospora Indianol^nsis Small. Perennial, bright green. Stems 3-angled, 
5-12 dm. tall : leaves sheathing the base of the stem ; blades 4-8 mm. broad, Avith smooth 
margins : spikelets rather numerous, about 1 cm. long, aggregated into several dense 
panicled clusters 2-3 cm. broad : scales oval, broadly acuminate, deciduous : perianth- 
bristles surpassing the achene, persistent: achenes flattened and with impressed sides, about 
4 mm. long, each capped by a tubercle nearly 5 mm. long. 

On damp prairies, Indianola, Texas. Spring. 

4. Rynchospora cornicolata (Lam.) A. Gray. Perennial. Stems smooth, 1-2 mm. 
tall: leaf-blades flat, 1.5-4.5 dm. long, 6-16 mm. wide, rough-margined : umbels some- 
times 2-5 dm. broad : spikelets spindle-shaped, much over 1 cm. long when mature, 
clustered at the ends of the rays and raylets : primary rays sometimes 15 cm. long: scales 
lanceolate, thin, acute, light brown : perianth-bristles about 6, rigid, upwardly scabrous : 
style subulate from a broad base 2-4 times longer than the achene, upwardly scabrous, 
1-2.5 cm. long, much exserted beyond the scales when mature : achenes obovoid, flat, 4 mm. 
long, dark brown, smooth. 

In swamx)s, Delaware to Florida, Ohio, Missouri and Texas. Summer and fall.— A variety with 
perianth-bristles about twice as long as the achene and congested inflorescence is i?. corniculaia macro- 
stdchya (Torr.) Britton ; it extends north as far as Massachusetts. 

5. Rynchospora pusIUa M. A. Curtis. Perennial, bright green. Stems densely 
tufted, 0.5-3 dm. tall, filiform : leaves resembling the stems but more slender and curved : 
spikelets in 1-3 separate clusters, elliptic-ovoid, about 2 mm. long, often 3-flowered : scales 
broadly ovate to suborbicular : perianth-bristles wanting : achenes whitish, flat, lenticular, 
oblong-obovoid or cuneate-obovoid, about 1 mm. long, transversely wrinkled, not pinched 
at the base, each with an almost free tubercle. 

About pine-land swamps, Florida to Texas. Also in the West Indies. Sp ring and summer. 

6. Rynchospora divdrgens ]M. A. Curtis. Perennial, bright green. Stems densely 
tufted, filiform or wiry, 1-4 dm. tall : leaves resembling the stems but more slender, curved : 
spikelets elliptic to ovoid-elliptic, 3-3.5 mm. long, acute, in loose or rarely somewhat con- 
tracted corymbs : scales broadly elliptic or broadly ovate : perianth-bristles wanting : 

13 



191 



CYPERACEAE 



achenes plump-lenticular, orbicular-obovoid, pale, 0,5-O.S mm. long, reticulated, pinched 
at the base, each with a depressed sessile tubercle. 

In moist pine lands, South Carolina to Florida. Also In the Bahamas and the West Indies. Spring 
and summer. 

7. Rynchospora Chapmanii M. A. Curtis. Perennial, pale green. Stems densely 
tufted, 2-6 dm. tall, filiform : leaves resembling the stem but more slender : spikelets ag- 
gregated into a solitary terminal cluster 1-1.5 cm. broad, spindle-shaped, 3-4 mm. long, 
whitish, 1-floAvered : scales 5, acuminate or awn-tipped, the upper one fertile : perianth- 
bristles wanting: achenes lenticular, oval, barely 1.5 mm. long, smooth and shining, each 
with a depressed-deltoid tubercle l-\ as long as the achene. 

In low pine lands, South Carolina to Florida and Louisiana. Spring to fall. 

8. Rynchospora pallida M. A. Curtis. Rootstocks slender : stems triangular, 3-6 
dm. tall: leaves various, the lower reduced to scales; blades 1-2.5 mm. wide, nearly 
smooth : spikelets numerous, spindle-shaped, 4-6 mm. long, aggregated in a compound 
terminal head, or occasionally also in a cluster from the upper axil : bracts with subulate 
blades : scales pale greenish brown, lanceolate, acuminate : perianth-bristles minute and 
early deciduous, or wanting : stigmas 2 : achenes lenticular, obovoid-oblong, smooth, brown, 
shining, 2 mm. long, or nearly so, each with a minute depressed tubercle. 

In pine-land bogs, Xew Jersey to North Carolina. Summer and fall. 

9. Rynchospora oligantha A. Gray. Eootstocks short : stems almost thread-like? 
leafy toward the base, 1.5-4 dm. tall: leaves few; blades filiform: spikelets solitary or 
2-4 together, terminal, narrowly oblong, acute, 6-8 mm. long, subtended by 1 or 2 filiform 
bracts : scales ovate, pale brown, acute, cuspidate : perianth-bristles usually 6, densely 
plumose below the middle : stigmas 2 : achenes obovoid, 2 mm. long or nearly so, obtuse, 
pale brown, dull, transversely wrinkled ; tubercle with a flat depressed border and a 
flattened conic acute projection. 

In wet sandy soil, Delaware to Florida and Texas. Summer. 

10. Rynchospora plumosa EIL Perennial, bright green. Stems tufted, 1.5-3.5 
dm. tall, slender and wiry : leaves few ; blades filiform, curving in nge : spikelets oblong- 
ovoid, 2.5-3.5 mm. long, in 3 or 4 lax clusters at the top of the stem : scales broadly ovate 
or oval : perianth-bristles 6, plumose nearly or quite to the top : achenes orbicular-obovoid, 
nearly 2 mm. long, including the depressed conic glabrous tubercle, strongly wrinkled. 

In dry pine lands, South Carolina to Florida and Louisiana. Spring to fall. 

11. Rynchospora intermedia (Chapm.) Britton. Perennial, bHght green. Stems 
tufted, 3-7 dm. tall, stout : leaves numerous at the base of the stem ; blades 1-2 mm. 
broad, more or less involute, with roughish margins : spikelets 3-4 mm. long, in 4-6 
clusters, forming a more or less interrupted terminal spike-like inflorescence : perianth- 
bristles plumose nearly or quite to the top: achenes obovoid, transversely wrinkled, more 
or less grooved, fully 2 mm. long ; tubercle depressed, conic, pubescent. [-B. plumosa yar, 
intermedia Chapm.] 

In pine lands, Florida. Spring to fall. 

12. Rynchospora semiplumosa A. Gray. Perennial, bright green. Stems tufted, 
2.5-7 dm. tall, rather rigid: leaves rather numerous at the base of the stem; blades 
1.5-2.5 mm. wide, often with roughish margins: spikelets croM^ded into a solitary terminal 
head, or with an additional cluster farther down the stem : perianth-bristles plumose below 
the middle or only near the base : achenes globose-obovoid, wrinkled, 1.5 mm. long ; tuber- 
cle broadly conic, glabrous. 

In pine lands, Georgia and Florida to Louisiana and Texas. Spring to fall. 

13. Rynchospora dlba (L. ^ Vahl. Pale green. Eootstocks short: stems slender 
or filiform, glabrous, 1.5-5 dm. tall : leaves bristle-like or slender, 0.5-1 mm. wide, shorter 
than the stem : spikelets in 1-4 dense corymbose clusters, narrowly oblong, acute at both 
ends, 4-G mm. long : scales ovate or ovate-lanceolate, white or pale green, acute : perianth- 
bristles 9-15, downwardly barbed, slender, about as long as the achene and tubercle : 
achenes obovoid-oblong, fully 1.5 mm. long, smooth, pale brown, lenticular ; tubercle lan- 
ceolate, flat, J as long as the achene. 

In bogs, Xewfoundlaud to Alaska, Florida, Kentncky, Minnesota and Oregon. Also in northern 
Europe and Asia. Summer. — A variety ranging from Georgia and Florida to Texas, with stouter stems, 
15-24 bristles and clusters of spikelets sometimes 3 cm. broad, is E. aiha mdcra Clarke. 

14. Rynchospora glomerata (L. ) Vahl. Deep green. Eootstocks slender: stems 
smooth, 3-10 dm. hi^h : leaves shorter than the stem ; blades flat, 2-4 mm. wide, rough- 
margined: spikelets in 3-7 corymbose-capitate axillary clusters, oblong, narrowed at both 
ends, 3-4 mm. long: scales lanceolate, dark brown: perianth-bristles 6, downwardly 



CYPERACEAE 



195 



barbed: achenes obovoid, above the slender base, lenticular, about 1.5 mm. long, smooth, 
dark brown ; tubercle subulate, about as long as the achene. 

In moist soil, Maine to Ontario, Michigan, Florida and Texas. Summer and fall.— A relatively 
stent variety, with stems 1-1.5 mm. tall, wider leaf-blades, numerons spikelets in componnd clusters 
and achenes 2 mm. long, is R. glome rat a paniculdta (A.Gray) Chapm.; it ranges from Maryland to 
Florida and Louisiana. A relatively slender form, with stems only 6-9 dm. tall, and few distant simple 
peduncled clusters is i?, glomcrafa leptocdrpa Chapm.; it ranges from South Carolina to Florida and 
Alabama. A third variety, R. (jlomerata discffilens Clarke, has smooth bristles or these barbed only near 
the apex, and a known range from New Jersey to North Carolina. 

15. Rynchospora axillaris (Lam.) Britton. Perennial, Stems stout, 5-10 dm. tall : 
leaf-blades nearly flat, keeled, 2-3 mm. wide: spikelets spindle-shaped, 6-6 mm. long, 
nnmerons, in several sliort-pednncled axillary and terminal dense globose heads some- 
times 2 cm. in diameter: scales dark brown, ovate-oblong, acute: perianth-bristles f), 
downwardly barbed: achenes broadly obovoid above the contracted base, 2.5 mm. long, 
brown, smooth, lenticnlar ; tnbercle subnlate, about as long as tlie achene. 

In swamps, Long Island to Florida and Louisiana. Summer and fall. 

16. Rynchospora microc6phaIa Britton. Perennial, deep green. Stems tufted, 
slender, 3-14 dm. tall, smooth : leaves overtopped by the stem ; blades linear-filiform, in- 
volute, smooth: spikelets numerous, 3-3.5 mm. long, crowded into 2-4 short-pedunclcd 
compact globose heads about 1 cm. in diameter or smaller: scales acuminate, smooth, 
chestnut-colored : perianth-bristles G, downwardly barbed : achenes lenticular, obovoid, 
1.5 mm. long, smooth, margined; tubercle shorter than the achene, subulate-lanceolate. 
[J2. axillaris var. microcephala Britton.] 

In swamps or low grounds, New Jersey to Florida and Louisiana, Spring to fall. 

17. Rynchospora fuscoides Bocckl. Perennial, bright green. Stems tufted, 1.5-7 
dm. tall, slender: leaves several, chiefly at the base of the stem; blades flat, smooth; 
spikelets 2-2.5 mm. long, in small often geminate terminal clusters and on robust plants 
with an additional one lower down the stem : perianth-bristles 6, barbed upward : achenes 
lenticular, smooth, about 2 mm. long excluding the subulate conic ciliate tubercle, mostly 
surpassed by the bristles. 

In low pine lands, Florida to Texas. Also in Cuba. Spring to fall. 

18. Rynchospora Curtissii Britton. Stems filiform, glabrous, 1-2 dm. tall : leaves 
few; blades filiform, less than 0.5 mm. Avide, much shorter than the stem: spikelets few 
or solitary, in 1-3 loose clusters, oblong, acnte at both ends, 4-6 mm. long : scales ovate- 
oblong, chestnut-brown, keeled, mucronate: perianth-bristles 6, slender, downwardly 
barbed, much overtopping the achene : achenes linear-oblong, nearly 1.5 mm. long, light 
brown, smooth, lenticular ; tubercle compressed, lanceolate, ciliate, dark brown, fully J as 
long as the achene. 

In bogs, Milton, Florida. Summer. 

19. Rynchospora filifolia Torr. Perennial, bright green. Stem tufted, 1.5-6 dm, 
tall, nearly terete, filiform or very slender : leaves numerous at the base of the stem ; blades 
filiform or bristle-like : spikelets aggregated into 2-4 capitate clusters, lanceolate in out- 
line, 3-3.5 mm. long: perianth-bristles barbed upward, rather rigid, not longer than the 
achene and tnbercle or scarcely so : achenes lenticular, obovoid, margined, smooth and 
shining, light brown, less than 1 mm. long ; tubercle flat, ciliate, triangular. 

About pine-land jxinds. North Carolina to Florida and Texas. Spring to fall. 

20. Rynchospora leptorhyncha C. Wright. Perennial, bright green. Stems tufted, 
slender, 3-6 dm. tall : leaves erect ; blades involute, filiform or linear-filiform, curved, 
smooth : spikelets lanceolate in outline, about 5 mm. long, acute, several together in 2 of 
3 rather loose capitate clusters : perianth-bristles 6, not longer than the achene and tubercle 
or scarcely so : achenes orbicular-obovoid or obovoid-oval, 1.5-2 mm. long, smooth, each 
capped by a lanceolate ciliate dark brown tubercle. 

In grassy pine woods, Florida and Cuba. Spring to fall. 

21. Rynchospora dfstans (Michx. ) Vahl. Perennial, pale green. Stems tufted, 
slender, 3-7 dm. tall : leaves several at the base of the stem ; blades filiform or nearly so 
by the involute margins: spikelets ovoid, about 3 mm. long, several together in terminal 
and axillary clusters : perianth-bristles mostly 6, usually upwardly barbed, about as long 
as the achene : achenes oval or oblong-oval, 1.5-2 mm. long, excluding the broad conic 
smooth tubercle. 

In pine lands. South Carolina to Florida. Spring to fall. 

22. Rynchospora gracil^nta A. Gray. Stems slender or filiform, smooth, 3-5 dm, 
tall : leaf -blades fiat or becoming involute in drying, rather less than 2 mm. wide, shorter 
than the stem : spikelets narrowly ovoid, acute, 4 mm. long, few, in 1-4 loose clusters, the 
lower clusters filiform stalked : scales ovate, brown : perianth-bristles 6, upwardly 



196 



CYPERACEAE 



barbed, much longer tlian tlie acliene : aclienes broadly oval or nearly orbicular, 1.5 mm. 
to nearly 2 mm. long, dark brown, lenticular, dull, smooth ; tubercle narrowly subulate, 
flat, widened at the base, pale, smooth, about as long as the achene. 

In pine-land swamps, New Jersey to Florida and Texas. Summer. 

23. Rynchospora Baldwinii A. Gray. Perennial, bright green. Stems somewhat 
tufted, stout, 6-12 dm. tall, sharply 3-angled : leaves several or numerous at the base of 
the stem, commonly over 1 dm. long; blades 2-7 mm. wide, attenuate, smooth or nearly 
so, more or less glaucous : spikelets ovoid or elliptic-ovoid, 5-6 mm. long, chestnut-col- 
ored, aggregated into 1-3 loosely capitate clusters : perianth-bristles 12-14, upwardly 
barbed, fully as long as the achene : achenes oval or orbicular-oval, minutely granular, 
fully 2 nun. long, excluding the triangular-conic smooth tubercle. 

In low pine lands, North Carolina to Georgia and Florida. Spring to fall. 

24. Rynchospora fascicularis (Michx. ) Vahl. Perennial, light green. Stems 
sparingly tufted, 6-12 dm. tall, obscurely 3-angled : leaves several at the base of the stem ; 
blades 1.5-3 mm. broad from a dilated base, or rarely slightly wider, more or less^ invo- 
lute : spikelets about 2-3 mm. long, acuminate, lanceolate in outline, aggregated in 2-5 
remote sometimes compound clusters: perianth-bristles much shorter than the achene, up- 
wardly barbed : achenes lenticular, oval or orbicular-oval, 2 mm. long excluding the trir- 
angular smooth much flattened tubercle. 

In low pine lands, South Carolina to Florida and Louisiana. Spring to fall. 

25. Ryncliospora brachychafeta Sauv. Perennial, pale green. Stems tufted, very 
slender or nearly filiform, spreading or procumbent, 2-4 dm, long : leaves several at the 
base of the stem ; blades involute, thus bristle-like or filiform : spikelets ovoid, about 4-5 
mm. long, usually few together in a small terminal cluster : perianth-bristles 3-6, upwardly 
barbed, much shorter than the achene : achenes lenticular, suborbicular, fully 2 ram, long 
including the triangular tubercle, granular, dark brown, twice or thrice as long as the 
bristles. 

In low pine lands, Kortli Carolina to Florida. Also in Cuba. Spring to fall, 

26. Ryncbospora dodecdndra Baldw, Perennial, yellowish green. Stems some- 
what tufted, 5-12 dm. tall, 3-angled : leaves crowded at the base of the stem ; blades 4-10 
mm. wide, rather rigid, smooth : spikelets ovoid, 6-8 mm. long, several in 4-6 rather open 
corymbs : perianth-bristles 6-10, upwardly barbed, shorter than the achene : achenes len- 
ticular, orbicular-obovoid or oval, smooth, 3-4 mm. long excluding the depressed nipple- 
like tubercle which is surrounded by a collar-like base, the body barely twice as long as the 
bristles. [i2. megalocarpa A, Gray.] 

In dry sand, North Carolina to Florida and Mississippi. Spring to fall. 

27. Rynchospora ciliata (Michx.) Vahl. Perennial, light green. Stems not densely 
tufted, 3-8 dm. tall, bluntly 3-angled, smooth : leaves often numerous at the base of the 
stem, mostly less than 1 dm. long ; blades broadly linear, 5-8 mm. wide, ciliate, glaucous, 
blunt or merely acute : spikelets narrowly ovoid or lanceolate in outline, 5-6 mm. long, 
usually aggregated into a solitary terminal capitate cluster : perianth-bristles 6, ^ as long 
as the achene : achenes lenticular, cancellate, oval or orbicular-oval, 1.5 mm. long ; tuber- 
cle rather depressed, conic. 

In low pine lands, North Carolina to Florida and Mississippi. Spring to fall. 

28. Rynchospora Gray! Kunth. Perennial, light green. Stems often solitary, 
3-7 dm. tall, relatively slender : leaves several or numerous at the base of the stem ; blades 
narrowly linear, 1.5-3 mm. long, smooth, attenuate : spikelets ovoid, 5-6 mm. long, light 
chestnut-colored, aggregated into usually 2-4 capitate clusters : perianth -bristles 6, as long 
as the achene and tubercle : achenes lenticular, plump, cancellate, obovoid, or broadly ob- 
long, 2-5 mm. long, dark brown ; tubercle depressed-conic, overtopped by the bristles. 

In drj' pine lands, North Carolina to Florida and Texas. Spring to fall. 

29. Rynchospora Pldnkii Britton. Perennial, bright green. Stems more or less 
tufted, 1.5-4 dm. tall, slender: leaves mainly basal; blades narrowly linear, attenuate, 
1.5-4 mm. wide, smooth, flat or nearly so: spikelets ovoid, 2.5-3 mm. long, chestnut -colored, 
acute or acuminate, aggregated into 1 or few clusters : perianth-bristles 6, much shorter 
than the achene, often about ^ as long: achenes obovoid or orbicular-obovoid, about 1.5 
mm. long, cancellate, brown, each surmounted by a depressed tubercle Avith a collar-like 
base. 

On plains and prairies, Arkansas and Texas. Spring and summer. 

30. Rynchospora rariflora Ell. Perennial, bright green. Stems densely tufted, 
2-5 dm. long, sometimes reclining, filiform, smooth : leaves involute-filiform or bristle- 
like, smooth : spikelets elliptic or ovoid, few in 2 or 3 lax filiform-peduncled corymbs : 
perianth-bristles 6, fragile, shorter than the achene : achenes lenticular, obovoid or broadly 



CYPERACEAE 



197 



elliptic, fully 1.5 mm. long, strongly transversely wrinkled, about twice as long as the 
bristles ; tubercle low-conic. 

In grassy pine lands, North Carolina to Florida and Texas. Spring to fall. 

31. Ryachospora Torreyana A. Gray. Stems terete or obscurely 3-angleil, smooth, 
slender, 4-9 dm. tall : leaf-blades involute, the lower 3-4 mm. wide at the base, elongated, 
the upper bristle-like, distant : spikelets ovoid, 3 mm. long, peduncled, numerous in 1-4 
loose distant clusters: scales brown, ovate, mucronate : perianth-bristles G, upwardly barbed : 
achenes flat, oblong-obovate, transversely wrinkled ; tubercle flat, conic, 1-J as long as the 
achene and continuous with it. 

In wet pine lands, New Jersey to South Carolina. Summer. 

32. Rynchospora Earlei Britton. Perennial, light green. Stems 3-8 dm. tall, 
smooth : leaves mainly at tlie base of the stem ; blades narrowly linear, 1.5-3 mm. broad, 
smooth : spikelets ovoid, 3.5-4 mm. long, acute, 2-6 in several cymose clusters on rela- 
tively stout peduncles : scales red, acute or apicnlate : perianth-bristles 6, shorter than the 
achene; achenes strongly biconvex, broadly obovoid, 2 mm. long, transversely wrinkled, 
reddish brown, constricted under the much depressed or nearly flat tubercle. 

In pine woods, Marshall ville, Georgia. Summer. 

33. Rynchospora perpl^xa Britton. Perennial, deep green. Stems slender, 5-11 
dm. tall, often tufted : leaves mostly at the base of the stem ; blades narrowly linear, flat, 
1-2.5 mm. wide, usually much elongated, smooth : spikelets ovoid or orbicular-ovoid, about 
2 mm. long, in a terminal and 1 or several axillary lax or rarely slightly congested corymbs 
on very slender peduncles ; scales brown, blunt or merely acute : perianth-bristles 6, 
shorter than the achene : achenes biconvex, not constricted under the tubercle, about 1 mm. 
long ; tubercle depressed, wider than high. 

In swamps and hammocks, North Carolina to Florida. Summer. 

34. Rynchospora cymosa Ell. Light green. Stems tufted, 3-anglcd, smooth, 3-8 dm. 
tall : leaf-blades flat, narrowly linear, grass-like, 3-4 mm. wide or the basal ones broader : 
bracts setaceous : spikelets ovoid-oblong, acute, 3 mm. long, sessile or nearly so, capitate 
in 2's-7's on the ultimate branches of the axillary and terminal clusters : scales dark 
brown, broadly ovate : perianth-bristles 6, upwardly barbed, shorter than the achene : 
achenes broadly obovoid or oblong-obovoid, lenticular, 1.5 mm. long, transversely wrinkled ; 
tubercle conic, about as high as wide, }-^ as long as the achene. 

In moist soil, New Jersey to Kentucky, Missouri, Florida and Texas. Also in Cuba. Summer.— A 
variety with stems 1.5-3.5 dm. tall, corymbs of few ovoid-globose dark brown spikelets and more deeply 
wrinkled achenes 1 mm. long, is J?, a^pnosn globuldris Chapm.; it ranges from Florida to Louisiana. 

35. Rynchospora compr^ssa Carey. Perennial, pale green. Stems tufted, 6-12 dm. 
tall, 3-angled : leaves several at the base of the stem ; blades rather rigid, 3-5 mm. broad, 
smooth or nearly so : spikelets ovoid, 2-2.5 mm, long, numerous, in 3-5 peduncled 
corymbs : perianth-bristles G, shorter than the achene : achenes lenticular, flat, 2 mm. 
long, coarsely transversely wrinkled, rhombic-obovoid, topped by a low conic tubercle with 
a collar-like base, about twice as long as the bristles, contracted under the tubercle. 

About pine-land ponds, Florida and Alabama. Spring to fall. 

36. Rynchospora patula A. Gray. Perennial, bright green. Stems somewhat 
tufted, 6-12 dm. tall, smooth, quite slender : leaves mainly on the lower part of the stem ; 
blades narrowly linear, 2-6 mm. wide, smooth: spikelets ovoid, 3-3.5 mm, long, 1-3- 
flowered, acute, many in terminal and axillary slender-peduncled compound corymbs : 
scales brown, deciduous : perianth-bristles not longer than the achene and tubercle : achenes 
lenticular, obovoid or orbicular-obovoid, barely 1.5 mm. long, transversely wrinkled ; tu- 
bercle setose, surpassing the perianth-bristles. 

In sandy pine woods and swamps, North Carolina lo Florida. Spring to fall. 

* 37. Rynchospora caduca Ell. Perennial, bright green. Stems often loosely tufted, 
8-15 dm. tall, sharply 3-angIed : leaves elongated ; blades 4-10 mm. wide, attenuate, 
rough -margined : spikelets ovoid, about 4 mm. long, numerous in 4-6 compound corymbs : 
perianth-bristles 6, longer than the achene and tubercle : achenes lenticular, orbicular- 
obovoid, about 1.5 mm. long, finely transversely wrinkled, surpassed by the slender bris- 
tles ; tubercle setose, conic. 

In swamps and on shaded banks, North Carolina to Arkansas, Florida and Texas. Spring to fall. 

38. Rynchospora mixta Britton. Perennial, pale or light green. Stems loosely 
tufted, 3-angled : leaves mostly at the base of the stem ; blades 3-7 mm. wide, slightly 
rough on the margins: spikelets 1-3-flowered, lanceolate in outline, 3.5-4 mm. long, 
acute, in slender-peduncled lax corymbs : scales few, erect : perianth-bristles 6, longer than 
the achene and tubercle : achenes' lenticulnr, narrowly obovoid, less than 1.5 mm. long, 
transversely wrinkled, about ^ as long as the slender bristles ; tubercle depressed-conic, setose. 

In river swamps and low pine lands, Georgia and Florida. Spring to fall. 



198 



CYPERACEAE 



39. Rynchospora prolifera Small. Perennial, bright green. Stems tuftedj slender, 
4-10 dm. tall, Aveak, smooth : leaf-blades elongated, 2-5 mm. wide, pale green : spike- 
lets numerous, in open corymbs, on filiform peduncles, flat, oblong-ovoid, 6-8 mm. long, 
acute, 5-10-flowcred : scales very tliin, spreading, early deciduous: perianth-bristles 0, 
fully as long as the achene and tubercle : aclienes lenticular, obovoid to suborbicuhir, 
slightly transversely wrinkled, reddish brown, fully 1-1.5 mm. long, persistent on the 
finally naked rachis ; tubercle conic, setose. 

In pine woods and sandy places, North Carolina to Florida and Mississippi. Summer. • 

40. Rynchospora punctata Ell. Perennial, pale green. Stems tufted, 3-7 dm. tall, 
3-angled, slender : leaves several at the base of the stem ; blades 2-4 mm. wide, slightly 
channeled, rough-margined : spikelets in several small clusters near the top of the stem, 
3-4 mm. long, acute : perianth-bristles 6, longer than the achene and tubercle : achenes 
lenticuhir, obovoid, barely 2 mm. long, prominently transversely wrinkled, surpassed by 
the bristles ; tubercle triangular, smooth. 

In pine lands, South Carolina and Georgia. Spring to fall. 

41. Rynchospora microcarpa Baldw. Perennial, bright green. Stems tufted, 
5-10 dm. tall, smooth : leaves mostly at the base of the stem ; blades channeled, 1.5-4 mm. 
wide, attenuate: spikelets ovoid, 2-3 mm. long, numerous in 4-6 compound corvmbs : 
perianth-bristles 5 or 6, not longer than the achene or but little longer ; achenes lenticular, 
broadly or orbicular-obovoid, barely 1 mm. long, strongly transversely wrinkled, about as 
long as the bristles or surpassing them ; tubercle bluntish, rather depressed. 

On pond margins in pine lauds, North Carolina to Florida and Texas. Also in the Bahamas. 
Spring to fall. 

42. Rynchospora decurrens Chapm. Perennial, pale green. Stems often loosely 
tufted, 6-12 dm. tall, arching above ; leaves mostly numerous at the base of the stem ; 
blades conspicuously elongated, lax, 2-4 mm, broad, glaucescent, smooth : spikelets ovoid, 
2-2.5 mm. long, filiform-peduncled, in 5-6 remote spreading or drooping lax corymbs: 
perianth-bristles 6 : achenes lenticular, narrowly obovoid or cuneate-obovoid, about 1 mm. 
long, transversely wrinkled, as long as the bristles or longer, each with the triangular 
sharp-pointed tubercle decurrent some distance on its sides. 

On muddy hanks, western Florida. Summer. 

43. Rynchospora schoenoides (Ell.) Britton. Perennial, bright green. Stems 
loosely tufted, 3-angled, 6-12 dm. tall : leaves elongated, sometimes numerous at the base of 
tlie stem ; blades smooth, or roughish on the margins: spikelets ovoid, 2.5-3 mm. long, 
numerous, in 3-5 compound more or less lax corymbs : perianth-bristles 6, as lon^ as the 
acliene and tubercle or longer : aclienes lenticular, oval, strongly transversely wrinkled, 
fully 1 mm. long ; tubercle smooth. 

Ahout pine-land pools, North Carolina to Florida and Louisiana. Spring to fall. 

44. Rynchospora miliacea (Lam.) A. Gray. Perennial, light green. Stems loosely 
tufted, 3-angled, 6-15 dm. tall : leaves often numerous at the base of the stem ; blades 
elongated, 3-8 mm, long, smooth : spikelets numerous, ovoid, 2.5-3 mm. long, peduncled, 
in 6-8 open spreading corymbs : scales deciduous ; perianth-bristles 6 : achenes 2-4 in each 
spikelet, lenticular, obovoid or oval, fully 1 mm. or rarely nearly 1.5 mm. long, pale, trans- 
versely wrinkled, about as long as the bristles, persistent ; tubercle smooth, depressed- 
conic. 

In bogs and miry localities, Florida to Louisiana, and in the West Indies. Spring to fall. 

45. Rynchospora stipitkta Chapm. Perennial, bright green. Stems tufted, 8-10 dm. 
tall, arching above, 3-angled: leaves numerous at the base of the stem ; blades conspic- 
uously elongated, 4-10 mm. wide, smooth : spikelets 7-8 mm. long, narrowly ovoid, 
numerous, in 4-5 compound drooping corymbs : perianth-bristles 6, upwardly barbed : 
achenes lenticular, 1-3 in a spikelet, orbicular-obovoid, stalked, the body about 1.5 mm. 
long, finely transversely wrinkled, less than ^ as long as the bristles ; tubercle depressed, 
setose. 

In river swamps, Florida. Spring to fall. 

46. Rynchospora stenophylla Chapm. Perennial, bright green. Stems tufted, 2-4 
dm. tall, wiry-filiform : leaves resembling the stems but more slender, smooth : spikelets 
lanceolate in outline, 4-5 mm. long, acute, relatively few, (5-7), in 1-3 lax, erect 
corymbs : perianth-bristles 6 : achenes lenticular, obovoid or obovoid-oblong, trans- 
versely wrinkled, 1.5 mm, long excluding the conic smooth tubercle whose summit the 
perianth-bristles barely equal. 

In grassy pine lands, Florida and Alabama. Spring to fall, 

47. Rynchospora inexpansa (Michx. ) Vahl. Eoot>tocks slender. vStems slender, 
3-angled, 5-9 dm. tall : leaves smooth ; blades 2 mm. wide or less, flat, the lower elon- 



CYPERACEAE 



199 



gated, the upper more slender, remote : spikelets fusiform, acute at both ends, about 6 
mm. long, numerous in 1-4 narrow finally drooping panicles : scales brown, lanceolate, 
acuminate: periantli-bristles 6, upwardly hispid, very slender, about twice as long ag the 
achene : achenes linear-oblong or oblanceolate, 2 mm. long, transversely wrinkled ; tuber- 
cle flat, triangular-subulate, J as long as the achene-body, setose. 

In moist soil, Virginia to Florida and Louisiana. Summer. 



7. S. trichopoda. 



20. SCIiERIA l'>erg. 

Mostly perennial caulescent herbs. Spikelets small, clustered in terminal, or terminal 
and axillary fascicles, or sometimes interruptedly glomerate-spicate. Flowers monoecious. 
Fertile spikelets 1-flowered. Staminate spikelets many-flowered. Scales imbricated, the 
1-3 lower and sometimes also the upper ones of the pistillate spikelets empty. Perianth 
none. Stamens 1-3. Style slender or sometimes swollen at the base, deciduous. Stigmas 
3. Ovary supported by a disk (hypogynium), or this wanting. Achenes globose or 
ovoid, obtuse, crustaceous or bony, white in our species. Nut Rush. 

Inflorescence of 1 or several terminal or lateral clusters. 

Inflorescence a single terminal clvister : hypogynium wanting. 

Achenes 2-3 mm. long, obtuse, with 2 pits in each side of the 3-angled base. 1^ S, gracilis, 
Achenes 4 mm. long, acute, without pits. 2. S. BaldwiniL 

Inflorescence of terminal and axillary clusters. 
Achene smooth. 

Hypogynium present, 3-angled : leaf-blades 3-9 mm. wide. 

HypoKynium covered with a rough white crust. 3. 5. triglomeraia. 

HypoCTi^iuJ^ supporting 8 or 9 tubercles. 4. S, oUgmiiha, 

Hypogynium wanting : leaf-blades 1.5-2.5 mm. wide. 5. S^ Hfhospcrraa, 

Achene reticulated, ridged or papillose. 
Achene reticulated or irregularly ridged. 

Hypogynium 3-lobed, appressed to the base of the achene. 

Clusters of spikelets sessile or nearly so : achene not hairy. 6. iS^. reticularis. 

Lower clusters of spikelets filiform-peduncled : achene hairy. 
Achene regularly reticulated 
Achene irregularly rugose-reticulated to nearly smooth. 

Clusters of spikelets drooping. 8. 5. Torrcyana. 

Clusters of spikelets rigid, mostly erect. 9. S, hemifaphra, 

Hypogyniums supj)orting 6 tubercles arranged in pairs. 10. S. Cttrtism. 

Achene papillose. 

Hypogynium supporting 3 entire emarginate or 2-lobed tubercles. 

Plant pubescent : bracts very ciliate : achene 3 mm. long. 11. S, ciliata. 

Plant glabrous throughout : achene 2 mm. long. 12. S, glabra, 

Hypogynium supporting 6 distinct tubercles. 13. S. pauciflora. 

Inflorescence interruptedly glomerate-spicate. 

Achene with short transverse ridges or somewhat reticulated : plant annual. 14. S. verticillafa. 
Achene smooth : plant perennial. 15. 5. hirtcUa. 

1. Scleria gracilis Ell. Perennial. Stems tufted, very slender or sometimes filiform, 
2-4 dm. tall, smooth : leaves few, shorter than the stem ; blades involute, filiform, smooth, 
simulating the stem : spikelets in a single terminal cluster : scales glabrous : achenes ovoid, 
2-3 mm. long, obtuse, shining or dull, distinctly ribbed lengthwise, with 2 pits on each 
side of the triangular base : hypogynium wanting. 

In low pine lands. South Carolina to Florida and Texas. Also in Cuba. Summer. 

2. Scleria Bald'wfnii Steud. Perennial. Stems relatively stout, 3-10 dm. tall, 
smooth, at least below, often rough above : leaves few ; blades linear, 2-5 mm. broad, or 
sometimes narrower, smooth or somewhat scabrous : spikelets in a single terminal cluster : 
scales glabrous : achenes ovoid, about 4 mm. long, smooth and even, dull, apiculate, ob- 
scurely triangular, without pits at the triangular base ; hypogynium wanting. 

In pine-laud swamps. Florida to Texas.— A form with longitudinally ribbed achenes, growing 
from Georgia and Florida to Texas, is S, Baldwlnii coatdta Britton, Summer, 

3. Scleria triglomer^ta Michx. Perennial. Stems 3-angled, 4-10 dm. tall : leaves 
few, but often conspicuous ; blades flat, glabrous or nearly so, 3-9 mm. wide, the upper at- 
tenuate, rarely exceeding the stem : flower clusters terminal, and usually also 1 or 2 smaller 
ones from the axils : achenes ovoid or ovoid-globose, above the hypogynium, obtuse, bony, 
obscurely 3-angled, smooth, bright white, shining, about 2 nmi. high ; hypogynium low, 
obtusely triangular, papillose-crustaceous. 

In meadows, thickets and dry sand, Vermont to Wisconsin, Florida, Texas and.Kansas. Summer 
and fall, 

4. Scleria oligdntha Michx. Perennial. Stems slender, erect, sharply 3-angled, 
nearly smooth, 4-9 dm. tall : leaves sometimes numerous in the tufts; blades smooth or 
slightly rough at the apex, 4r-6 mm. wide, the lower short, acute, the upper elongated : 
clusters terminal, usually also 1 or 2 axillary and filiform-stalked : bracts slightly ciliate 






200 



CYPERACEAE 



or glabrous : achenes ovoid above the hypogynium, obtuse but sometimes pointed, bright 
white, smooth, shining ; hypogynium a narrow obtusely triangular border supporting 8 or 
9 small tubercles under the achene-body. 

In moist soil, near the coast, Virginia to Florida and Texas. Summer. 

5. Selena lithosp^rma (L. ) Sw. Perennial. Stems slender, 3-6 dm. long, smooth : 
leaves quite numerous; blades narrowly linear, 1.5-2.5 mm. "wide, w-ith scabrous-ciliate 
margins and keel ; sheaths ciliate at the throat : spikelets in 2-4 distant interrupted 
spikes, the lower with leaf-like bracts, the upper with bristle-like bracts : scales lanceo- 
late, acuminate, rough at the apex : achenes |obovoid or oblong, about 1.5 mm. long, 
smooth and glossy, without pores ; hypogynium wanting. \_S. fihformis Sw.] 

m low pine lands, southern peninsular Florida. Also in nearly all tropical regions. 

6. Scleria reticularis Michx. Perennial. Stems slender, erect, 3-6 dm. tall : leaves 
few ; blades narrowly linear, glabrous or nearly so, 2-3 nnn. wide, not overtopping the 
stem : spikelets in a terminal cluster and 1-3 remote axillary sessile or nearly sessile clus- 
ters : bracts glabrous : achenes globose, dull white when mature, reticulated, 1 mm. in 
diameter, glabrous ; hypogynium 3-lobed, its lobes appressed to the base of the achene. 

In moist meadows, Massachusetts to Missouri and Florida. Also in Cuba. Summer and fall. 

7. Scleria trichdpoda C. Wright, Perennial, Stems tufted, often spreading, 2-7 
mm. long, smooth : leaves often quite numerous in the tufts ; blades linear, 2-4.5 mm. wide, 
usually with cartilaginous marginal ribs, rather abruptly pointed : clusters of spikelets 1- 
3 cm. long, the axillary ones filiform-peduncled : bracts glabrous: stigmas 8 : achenes glo- 
bose or slightly depressed above the 3-lobed appressed hypogynium, 2-2.5 mm. in diameter, 
regularly reticulated, somewhat pubescent. 

In low grounds and pine lands, New Jersey to Missouri, Florida, Texas and Mexico. Also in the 
West Indies. Spring to fall. 

8. Scleria Torrey^na Walp. Perennial. Stems weak, spreading or diffuse, nearly or 
quite smooth, 3-6 dm. long, relatively stout : leaves often few ; blades linear, nearly flat, 
glabrous, 3-8 mm. Avide, not exceeding the stem : spikelets in a loose terminal cluster, and 
1-3 filiform-stalked drooping axillary ones : bracts glabrous : achenes globose above the 3- 
lobed appressed hypogynium, somewhat pointed, 2-2.5 mm. in diameter, irregularly ru- 
gose-reticulated with low ridges, the ridges pubescent, and connected by shorter ones. 

In moist soil, southtrn New Jersey to Florida and Texas. Summer. 

9. Scleria hemitdphra Steud. Perennial. Stems slender, 1.5-8 dm. long, more or 
less tufted, glabrous or nearly so : leaves shorter than the stem ; blades flat, 1-4 mm, broad, 
attenuate : clusters of spikelets 2-4 cm. long or rarely smaller, rigid, or mostly erect, the 
bracts and scales conspicuous : stigmas 3 : achenes globular above the 3-lobed appressed 
hypogynium, 1.5-2 mm. in diameter, irregularly rugose-reticulated, abruptly pointed, 
minutely pubescent. 

In wet places or sandy swamps, Florida to Mississippi. Also in the West Indies, Mexico and Cen- 
tral America. Bummer and fall. 

10. Scleria Curtissii Britton. Perennial. Stems relatively slender, 1.5-4.5 dm. 
long, weak, glabrous or nearly so, loosely tufted on stout roostocks : leaves quite numer- 
ous in the tufts ; blades very narrowly linear, 1-2 mm. wide, smooth, attenuate, often not 



much thicker than the stem : clusters of spikelets few-flowered, the axillary ones, when 
present, slender-peduncled : scales scarious-margined : bracts ciliate : stigmas 3 : achenes 
globular or slightly depressed above the hypogynium, reticulated, 1.5-2 mm. in diameter, 
glabrous, shining, abruptly pointed ; hypogynium supporting 6 tubercles arranged in pairs. 

In pine lands, near Jacksonville, Florida. Summer and fall. 

11. Scleiia cili^ta Michx. Perennial. Stems slender or relatively stout, 3-6 dm. 
tall, pubescent especially on the angles above : leaves few or sometimes numerous at the 
base of the stem ; blades narrowly linear, very variable in width, sometimes pubescent, 
often glabrous ; sheaths pubescent : spikelets generally in clusters with conspicuously cil- 
iate bracts ; achenes subglobose or globose-ovoid, 3 mm. long, acute, roughened by unequal 
projections or short ridges, those near the base longer and deflected ; hypogynium a narrow 
obtusely 3-angled border supporting 3 entire or 2-lobed tubercles. [aS. Elliottii Chapm.] 

In pine lands, Virginia to Missouri, Florida and Texas. Also in the West Indies. Spring and 
summer. 

12. Scleria glabra (Chapm.) Britton. Perennial. Stems, like the rest of the foliage, 
glabrous, relatively slender, 2.5-9 dm. long, loosely tufted from horizontal rootstocks : 
leaves few ; blades often about as thick as the stem, sometimes 2-3 mm. wide : clusters of 
spikelets small and few-flowered : bracts and scales glabrous : stigmas 3 : achenes globular, 
or globose-ovoid above the hypogynium, about 2 mm. long, papillose : hypogynium sup- 
porting 3 entire or 2-lobed tubercles. [6'. pauciflora var. glabra Chapm.] 

In pine lands, North Carolina to Florida and Alabama. Also in the West Indies. Spring to fall, 



CYPERACEAE 



201 



13. Scleria pauciflora Muhl. Perennial, pubescent. Stems slender, erect, usually 
tufted, 2-5 dm. tall : leaves commonly numerous in the tufts ; blades narrowly linear, less 
tlian 2 mm. wide, the upper elongated and often overtopping the stem, their sheuths often 
densely puberulent and pubescent : spikelets in a small terminal cluster and in 1 or 2 
axillary ones: achenes globular, 1.5-2 jnm, in diameter, papillose, the lower; papillae 
elongated and reflexed ; hypogynium a narrow obtusely triangular border supporting 6 dis- 
tinct tubercles. 

In dry soil, New Hampshire to Missouri, Florida and Texas. Also in Cuba. Summer and fall. 

14. Scleria verticill^ta MuliL Annual. Stems very slender or filiform, smootli or 

nearly so, erect, 1-5 dm. tall : leaves numerous in the tufts ; blades very narrowly linear, 

0.5-1 mm. wide, erect, weak, shorter than the stem : spikelets in several separated clusters : 

bracts bristle-like : scales glabrous : achenes globose, fully 1 mm. in diameter, with short 

transverse ridges or somewliat reticulated : hypogynium none. Plant, especially the roots, 

fragrant in drying. 

In moist meadows, eastern Massachusetts to Ontario and Michigan, Florida, Texas and Mexico. 
Also in the West Indies. Summer and fall. 

15. Scleria hirt^lla Sw. Perennial. Stems slender, 1-6 dm. long, smooth or nearly 
so : leaves extending well up on the stem ; blades linear, mostly 2-4 mm. wide, like the 
sheaths, pubescent : spikelets in 4-8 sessile sometimes nodding clusters : scales various ; 
those of staminate flowers pointless ; those of pistillate flowers broader, cuspidate, glabrous : 
achenes sulglobose, 1-1.5 mm. in diameter, pointed, smooth, slightly pinched at the tri- 
angular base, each side of which is furnished with 5-7 minute pores : hypogynium want- 
ing. 

In low pine lands, South Carolina to Florida and Louisiana. Also in tropical America. Summer. 

21. CAREX L. 

Grass-like herbs, perennial by rootstocks. Stems or scapes mo3tly 3-angled and 
tufted. Leaves 3-ranked. Bracts elongated or very short, subtending the spikes, or want- 
ing. Flowers monoecious or dioecious, solitary in the axils of small bracts (scales). Spikes 
either wholly pistillate, wholly staminate, or bearing both staminate and pistillate flowers 
(androgynous). Perianth wanting. Staminate flowers of 3 stamens: filaments filiform. 
Pistillate flowers of a single pistil with a style and 2 or 3 stigmas, borne on a verv short 



axis in the axil of a sac-like bractlet or second bract called the perigynium (utricle), whicl 
completely encloses the achene. Achene 3-angled, lenticular or plano-convex. Skdge. 

A. Staminate flowers numerous, in one or more terminal splices, which are sometimes pistillate at the 
base or summit, or the spike solitary and the stamhiate flowers terminal or basal, rarely dioecious : 
stigmas mostly 3 and the achene 3-angled or swollen (stigmas 2 and the achene lenticular or com- 
pressed in nos. 29-30). EUCAREX.- 
♦Perigynia mostly long-beaked, 3-20 mm. long, often inflated, the beak usually as long as the body 

or longer (short-beaked in no. 20); pistillate spikes mostly large, globose, ovoid, oblong or cylin- 
dric. 

Perigynia membranous or papery. 

Perigynia ovoid, conic, each with a narrowed base, or subulate, tapering into the beak. 
Teeth of the perigj'nium-beak slender, short or none, not stiff nor awned. 

Teeth of the perigynium-beak lanceolate or subulate. I. LUPULINAE. 

Teeth of the perigynium-beak short or almost wanting. II. VESICARIAE. 

III. PSEUDOCYPERINAE. 



Teeth of the perigynium-beak stiff, setaceous or awned. 
Perigynia obo void, veryjabruptly contracted into the beak ; 



spikes exceedingly dense IV. SQUARROSAE. 

Perigynia firm, hard or leathery. V. PALUDOSAK 

** Perigynia short-beaked or beakless, little or not at all inflated, 1-5 mm. long, the beak commonly 
not more than y^ as long as the body (long-beaked in no. 27): spikes small and oblong or glo- 
bose ; or elongated, linear or narrowly cylindric. 
t Spikes 2 or more, the staminate one always uppermost, sometimes partly pistillate. 

I Pistillate spike or spikes many-flowered, mostly 2.5 cm. long or more (or shorter in nos. 28, 37, 
39, 40, 44, 51-54), linear, narrowly cylindric or oblong. 
Perigynium with a straight short beak (long-beaked in no. 27 ; nearly beakless in no. 21), firm 

or leathery in texture : pistillate spikes erect : stigmas 3. 
^ Uppermost spike staminate from the oase to about the 

middle. VI. SHORTIANAE. 

Uppermost spike entirely staminate, or occasionally 

pistillate at the base. 
Perigvnia papillose; beak very short, nearly or 

quite entire. ^ VII. ANOMALAE. 

Perigynia pubescent (sometimes glabrous in no. ' 

24); beak sharply 2-toothed. VIII. HIRTAE. 

Perigynium beakless or very short-beaked (see no. 21), and with orifice nearly or quite entire, 
thin in texture, not inflated, closely investing the achene : pistillate spikes erect or 
drooping, often brown or purple : stigmas often 2, 
Pistillate spikes erect or somewhat spreading. 

Terminal spike staminate below : stigmas 3. IX. ATRATAE. 

Terminal spike staminate throughout; stigmas 2, X. RIGIDAE. 



202 



CYPERACEAE 



Pis.tillate spikes drooping, mostly on slender peduncles (erect in no. 35). 
Pistillate spikes O.G-7.5 cm. long : stigmas 3 (2 in no. 30). 
Pistillate spikes linear : scales shorter than the perigynia. 

XI. FKASINAE. 



Pistillate spikes globose, oblong or cylindric : 
scales as long as the perigynia, or longer. 
Pistillate spikes 2.5-10 cm. long : scales 1-8 times 
as long as the perigynia. 
Perigynium tapering tea distinct beak (nearly or quite 
beaklessin nos. 37-41), membranous in texture (firm 
in no. 50), inflated or loosely investing the achene ; 
pistillate spikes mostly drooping, often narrowly 
linear. 
Terminal spike staminate below, pistillate above: 
beak of the perigynium short or none. 
Spikes all erect or nearly so. 

Pistillate spikes drooping or spreading (erect or 
little spreading in no. 42). 
Terminal spike entirely staminate, or sometimes pis- 
tillate at the base. 
Leaves pubescent. 
Leaves glabrous. 

Perigynia manifestly beaked, nerved or nerve- 
less: pistillate spikes drooping. 

Perigynia beakless or minutely beaked, finely 
many-striate : spikes erect or nearly so. 



XIL PEXDULIXAE. 
XIIL CRYPTOCAKPAE. 



XIV. VIRESCEXTES. 
XV. GRACILLIMAE. 



XVI. FLEXILES. 



XVII. DEBILES. 
XVIIL GRISEAE. 



g§ Pistillate spikes small, few-many-flowered, mostly 6-25 
mm. long (sometimes longer in no. 60). (See also nos. 

28,37,39,40.44,51-54.) 

Perig^'nia glabrous. 

Pistillate spikes many-flowered, 6-25 mm. long, usu- 
ally dense. 
Pistillate spikes few-several-flowered, often loose. 
Scales of the spike normal, neither elongated nor 
leaf-like. 
Leaf-blades2-36mm. wade: bracts leaf-like, usu- 
ally large. 
Perigynia finely many-striate. 
Perigynia with few or many, mostly strong, 
nerves. 
Leaf-bla-des and stems mostly capillary : bracts 
mere bladeless sheaths. 
Scales of the spikes elongated, leaf-like. 
Perigynia i)ubescent. 

Perigynia mostly rounded. 
Perigynia conspicuously 3-angled. 

ft Spikes solitary, sometimes dioecious. 
Leaf-blades 2-5 cm. wide, leathery. 
Leaf-blades 0.5-6 mm. wide, not leathery. 

Staminate and pistillate flowers on different scapes. 
Staminate and pistillate flowers in the same spike. 
Scales of the spikes elongated, leaf-like. 
Scales of the spikes short, normal. 
Perigynia obtuse : swamp species. 
Perigynia beaked : prairie species. 



XIX. GRAXULARES. 



XX. OLIGOCARPAE. 
XXI. LAXIFLORAE. 

XXII. DIGITATAE. 
XXVII. PHYLLOSTACHYAE. 

XXIII. MONTANAE. 

XXIV. TRIQUETRAE. 



XXV. PHY^SOCEPHALAE. 

OCXVI. SCIRPINAE. 

XXVII. PHY'LLOSTACHY'AE 

XXVITL LEPTOCEPHALAE. 
XXIX. FILIFOLIAE. 




B. Staminate flowers few, at the summits or bases of the always sessile spikes, or sometimes forming 
whole spikes, or variously intermixed with the pistillate: stigmas always 2: achene lenticular, 
compressed, ellipsoid or plano-convex. VIGNEA. 
Staminate flowers at the summit of the spike. 

Spikes yellowish or brown at maturity, in compound or pan- 
icled clusters. 
Perigynia strongly several-nerved, especially on the outer 

face. 
Perigynia nerveless or faintly nerved. 
Spikes green or greenish when mature, aggregated or sepa- 
rated, in simple clusters. 
Staminate flowers at